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Haanstra JF, Dekker E, Cats A, Nagengast FM, Hardwick JC, Vanhoutvin SA, de Vos Tot Nederveen Cappel WH, Vasen HF, Kleibeuker JH, Koornstra JJ. Effect of chromoendoscopy in the proximal colon on colorectal neoplasia detection in Lynch syndrome: a multicenter randomized controlled trial. Gastrointest Endosc 2019; 90:624-632. [PMID: 31028782 DOI: 10.1016/j.gie.2019.04.227] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/16/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Patients with Lynch syndrome (LS) undergo regular surveillance by colonoscopy because of an increased risk of colorectal neoplasia, particularly in the proximal colon. Chromoendoscopy (CE) has been reported to improve neoplasia detection compared with conventional white-light endoscopy (WLE), but evidence is limited. Our aim was to investigate the effect of CE in the proximal colon on detection of neoplastic lesions during surveillance in LS. METHODS This was a multicenter prospective randomized controlled trial of 246 patients with LS who were randomly assigned (1:1) to conventional WLE (n = 123) or colonoscopy with CE in the proximal colon (n = 123), stratified for previous colorectal adenomas and enrolling center. Two years after baseline colonoscopy, patients underwent colonoscopy with CE in the proximal colon. The primary outcome was the proportion of patients with at least one neoplastic lesion at baseline and after 2 years. RESULTS Neoplasia detection rates at baseline colonoscopy were 27% for WLE versus 30% for CE (odds ratio [OR], 1.23; 95% confidence interval [CI], 0.69-2.2; P = .56). In the proximal colon, neoplasia detection rates were 16% for WLE versus 24% for CE (OR, 1.6; 95% CI, 0.9-3.1; P = .13). Total procedure time was 9 minutes longer in the CE group. At follow-up after 2 years, neoplasia detection rates were similar in both groups: 26% for the original WLE group versus 28% for the CE group (OR, 1.1; P = .81). CONCLUSIONS CE in the proximal colon for LS surveillance was not superior to WLE with respect to the initial detection of neoplasia, and not associated with reduced neoplasia detection rates after 2 years. The value of CE remains to be established. (Clinical trial registration number: NCT00905710.).
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Affiliation(s)
- Jasmijn F Haanstra
- Department of Gastroenterology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands; Department of Gastroenterology, Isala Clinics, Zwolle, the Netherlands
| | - Evelien Dekker
- Department of Gastroenterology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Annemieke Cats
- Department of Gastroenterology, the Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Fokko M Nagengast
- Department of Gastroenterology, Radboud University Nijmegen Medical Center, Nijmegen, the Netherlands
| | - James C Hardwick
- Department of Gastroenterology, Leiden University Medical Center, Leiden, the Netherlands
| | - Steven A Vanhoutvin
- Department of Gastroenterology, the Netherlands Cancer Institute, Amsterdam, the Netherlands
| | | | - Hans F Vasen
- Department of Gastroenterology, Leiden University Medical Center, Leiden, the Netherlands; The Netherlands Foundation for the Detection of Hereditary Tumours, Leiden, the Netherlands
| | - Jan H Kleibeuker
- Department of Gastroenterology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
| | - Jan J Koornstra
- Department of Gastroenterology, University Medical Center Groningen, University of Groningen, Groningen, the Netherlands
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2
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Barendse RM, Musters GD, de Graaf EJR, van den Broek FJC, Consten ECJ, Doornebosch PG, Hardwick JC, de Hingh IHJT, Hoff C, Jansen JM, van Milligen de Wit AWM, van der Schelling GP, Schoon EJ, Schwartz MP, Weusten BLAM, Dijkgraaf MG, Fockens P, Bemelman WA, Dekker E. Randomised controlled trial of transanal endoscopic microsurgery versus endoscopic mucosal resection for large rectal adenomas (TREND Study). Gut 2018; 67:837-846. [PMID: 28659349 DOI: 10.1136/gutjnl-2016-313101] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Revised: 05/02/2017] [Accepted: 05/03/2017] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Non-randomised studies suggest that endoscopic mucosal resection (EMR) is equally effective in removing large rectal adenomas as transanal endoscopic microsurgery (TEM), but EMR might be more cost-effective and safer. This trial compares the clinical outcome and cost-effectiveness of TEM and EMR for large rectal adenomas. DESIGN Patients with rectal adenomas ≥3 cm, without malignant features, were randomised (1:1) to EMR or TEM, allowing endoscopic removal of residual adenoma at 3 months. Unexpected malignancies were excluded postrandomisation. Primary outcomes were recurrence within 24 months (aiming to demonstrate non-inferiority of EMR, upper limit 10%) and the number of recurrence-free days alive and out of hospital. RESULTS Two hundred and four patients were treated in 18 university and community hospitals. Twenty-seven (13%) had unexpected cancer and were excluded from further analysis. Overall recurrence rates were 15% after EMR and 11% after TEM; statistical non-inferiority was not reached. The numbers of recurrence-free days alive and out of hospital were similar (EMR 609±209, TEM 652±188, p=0.16). Complications occurred in 18% (EMR) versus 26% (TEM) (p=0.23), with major complications occurring in 1% (EMR) versus 8% (TEM) (p=0.064). Quality-adjusted life years were equal in both groups. EMR was approximately €3000 cheaper and therefore more cost-effective. CONCLUSION Under the statistical assumptions of this study, non-inferiority of EMR could not be demonstrated. However, EMR may have potential as the primary method of choice due to a tendency of lower complication rates and a better cost-effectiveness ratio. The high rate of unexpected cancers should be dealt with in further studies.
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Affiliation(s)
- Renée M Barendse
- Department of Surgery, Academic Medical Centre, Amsterdam, Netherlands
| | | | | | | | | | | | - James C Hardwick
- Gastroenterology, Leiden University Medical Centre, Leiden, the Netherlands
| | | | - Chrisiaan Hoff
- Surgery, Medical Centre Leeuwarden, Leeuwarden, the Netherlands
| | - Jeroen M Jansen
- Gastroenterology, Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands
| | | | | | - Erik J Schoon
- Gastroenterology, Catharina Hospital, Eindhoven, the Netherlands
| | | | - Bas L A M Weusten
- Gastroenterology, St. Antonius Hospital, Nieuwegein, the Netherlands
| | | | - Paul Fockens
- Gastroenterology, Academic Medical Centre, Amsterdam, the Netherlands
| | - Willem A Bemelman
- Department of Surgery, Academic Medical Centre, Amsterdam, Netherlands
| | - Evelien Dekker
- Gastroenterology, Academic Medical Centre, Amsterdam, the Netherlands
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van Willigen DM, van den Berg NS, Buckle T, KleinJan GH, Hardwick JC, van der Poel HG, van Leeuwen FWB. Multispectral fluorescence guided surgery; a feasibility study in a phantom using a clinical-grade laparoscopic camera system. Am J Nucl Med Mol Imaging 2017; 7:138-147. [PMID: 28721307 PMCID: PMC5511123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 06/30/2017] [Indexed: 06/07/2023]
Abstract
Although the possibilities in image guided surgery are advancing rapidly, complex surgical procedures such as nerve sparing prostatectomy still lack precision regarding differentiation between diseased and delicate anatomical structures. Here, the use of complementary fluorescent tracers in combination with a dedicated multispectral fluorescence camera system could support differentiation between healthy and diseased tissue. In this study, we provide proof of concept data indicating how a modified clinical-grade fluorescence laparoscope can be used to sensitively detect white light and three fluorescent dyes (fluorescein, Cy5, and ICG) in a sequential fashion. Following detailed analysis of the system properties and detection capabilities, the potential of laparoscopic three-color multispectral imaging in combination with white light imaging is demonstrated in a phantom set-up for prostate cancer.
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Affiliation(s)
- Danny M van Willigen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - Nynke S van den Berg
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
- Department of Urology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek HospitalPlesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Tessa Buckle
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - Gijs H KleinJan
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
- Department of Nuclear Medicine, The Netherlands Cancer Institute-Antoni van Leeuwenhoek HospitalPlesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - James C Hardwick
- Department of Gastroenterology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
| | - Henk G van der Poel
- Department of Urology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek HospitalPlesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
| | - Fijs WB van Leeuwen
- Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical CenterAlbinusdreef 2, 2300 RC, Leiden, The Netherlands
- Department of Urology, The Netherlands Cancer Institute-Antoni van Leeuwenhoek HospitalPlesmanlaan 121, 1066 CX, Amsterdam, The Netherlands
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4
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Hoekstra E, Kodach LL, Das AM, Ruela-de-Sousa RR, Ferreira CV, Hardwick JC, van der Woude CJ, Peppelenbosch MP, Ten Hagen TLM, Fuhler GM. Low molecular weight protein tyrosine phosphatase (LMWPTP) upregulation mediates malignant potential in colorectal cancer. Oncotarget 2016; 6:8300-12. [PMID: 25811796 PMCID: PMC4480753 DOI: 10.18632/oncotarget.3224] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 01/26/2015] [Indexed: 12/27/2022] Open
Abstract
Phosphatases have long been regarded as tumor suppressors, however there is emerging evidence for a tumor initiating role for some phosphatases in several forms of cancer. Low Molecular Weight Protein Tyrosine Phosphatase (LMWPTP; acid phosphatase 1 [ACP1]) is an 18 kDa enzyme that influences the phosphorylation of signaling pathway mediators involved in cancer and is thus postulated to be a tumor-promoting enzyme, but neither unequivocal clinical evidence nor convincing mechanistic actions for a role of LMWPTP have been identified. In the present study, we show that LMWPTP expression is not only significantly increased in colorectal cancer (CRC), but also follows a step-wise increase in different levels of dysplasia. Chemical inhibition of LMWPTP significantly reduces CRC growth. Furthermore, downregulation of LMWPTP in CRC leads to a reduced migration ability in both 2D- and 3D-migration assays, and sensitizes tumor cells to the chemotherapeutic agent 5-FU. In conclusion, this study shows that LMWPTP is not only overexpressed in colorectal cancer, but it is correlated with the malignant potential of this cancer, suggesting that this phosphatase may act as a predictive biomaker of CRC stage and represents a rational novel target in the treatment of this disease.
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Affiliation(s)
- Elmer Hoekstra
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwa, Rotterdam, The Netherlands
| | - Liudmila L Kodach
- Department of Gastroenterology and Hepatology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Asha M Das
- Department of Surgery, Section Surgical Oncology, Laboratory Experimental Surgical Oncology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwal, Rotterdam, The Netherlands
| | - Roberta R Ruela-de-Sousa
- Department of Biochemistry, Institute of Biology, University of Campinas, Brazil (UNICAMP), Campinas, Sao Paulo, Brazil
| | - Carmen V Ferreira
- Department of Biochemistry, Institute of Biology, University of Campinas, Brazil (UNICAMP), Campinas, Sao Paulo, Brazil
| | - James C Hardwick
- Department of Gastroenterology and Hepatology, Cancer Genomics Centre Netherlands and Centre for Biomedical Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - C Janneke van der Woude
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwa, Rotterdam, The Netherlands
| | - Maikel P Peppelenbosch
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwa, Rotterdam, The Netherlands
| | - Timo L M Ten Hagen
- Department of Surgery, Section Surgical Oncology, Laboratory Experimental Surgical Oncology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwal, Rotterdam, The Netherlands
| | - Gwenny M Fuhler
- Department of Gastroenterology and Hepatology, Erasmus MC, University Medical Center Rotterdam, 's Gravendijkwa, Rotterdam, The Netherlands
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5
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Heijmans J, Muncan V, Jacobs RJ, de Jonge-Muller ESM, Graven L, Biemond I, Ederveen AG, Groothuis PG, Mosselman S, Hardwick JC, Hommes DW, van den Brink GR. Correction: Intestinal Tumorigenesis Is Not Affected by Progesterone Signaling in Rodent Models. PLoS One 2013; 8. [PMID: 29294471 PMCID: PMC6061774 DOI: 10.1371/annotation/b60d4ec5-4c6f-43ab-9f63-322e3cd59636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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6
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Hennink SD, Hofland N, Gopie JP, van der Kaa C, de Koning K, Nielsen M, Tops C, Morreau H, de Vos tot Nederveen Cappel WH, Langers AMJ, Hardwick JC, Gaarenstroom KN, Tollenaar RA, Veenendaal RA, Tibben A, Wijnen J, van Heck M, van Asperen C, Roukema AJ, Hommes DW, Hes FJ, Vasen HFA. Value-based healthcare in Lynch syndrome. Fam Cancer 2013; 12:347-54. [DOI: 10.1007/s10689-013-9655-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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7
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Heijmans J, van Lidth de Jeude JF, Koo BK, Rosekrans SL, Wielenga MCB, van de Wetering M, Ferrante M, Lee AS, Onderwater JJM, Paton JC, Paton AW, Mommaas AM, Kodach LL, Hardwick JC, Hommes DW, Clevers H, Muncan V, van den Brink GR. ER stress causes rapid loss of intestinal epithelial stemness through activation of the unfolded protein response. Cell Rep 2013; 3:1128-39. [PMID: 23545496 DOI: 10.1016/j.celrep.2013.02.031] [Citation(s) in RCA: 195] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2012] [Revised: 01/31/2013] [Accepted: 02/28/2013] [Indexed: 01/01/2023] Open
Abstract
Stem cells generate rapidly dividing transit-amplifying cells that have lost the capacity for self-renewal but cycle for a number of times until they exit the cell cycle and undergo terminal differentiation. We know very little of the type of signals that trigger the earliest steps of stem cell differentiation and mediate a stem cell to transit-amplifying cell transition. We show that in normal intestinal epithelium, endoplasmic reticulum (ER) stress and activity of the unfolded protein response (UPR) are induced at the transition from stem cell to transit-amplifying cell. Induction of ER stress causes loss of stemness in a Perk-eIF2α-dependent manner. Inhibition of Perk-eIF2α signaling results in stem cell accumulation in organoid culture of primary intestinal epithelium. Our findings show that the UPR plays an important role in the regulation of intestinal epithelial stem cell differentiation.
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Affiliation(s)
- Jarom Heijmans
- Tytgat Institute for Liver and Intestinal Research and Department of Gastroenterology and Hepatology, Academic Medical Center, 1105 AZ Amsterdam, the Netherlands
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8
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Liv N, Zonnevylle AC, Narvaez AC, Effting APJ, Voorneveld PW, Lucas MS, Hardwick JC, Wepf RA, Kruit P, Hoogenboom JP. Simultaneous correlative scanning electron and high-NA fluorescence microscopy. PLoS One 2013; 8:e55707. [PMID: 23409024 PMCID: PMC3568124 DOI: 10.1371/journal.pone.0055707] [Citation(s) in RCA: 82] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2012] [Accepted: 12/28/2012] [Indexed: 02/04/2023] Open
Abstract
Correlative light and electron microscopy (CLEM) is a unique method for investigating biological structure-function relations. With CLEM protein distributions visualized in fluorescence can be mapped onto the cellular ultrastructure measured with electron microscopy. Widespread application of correlative microscopy is hampered by elaborate experimental procedures related foremost to retrieving regions of interest in both modalities and/or compromises in integrated approaches. We present a novel approach to correlative microscopy, in which a high numerical aperture epi-fluorescence microscope and a scanning electron microscope illuminate the same area of a sample at the same time. This removes the need for retrieval of regions of interest leading to a drastic reduction of inspection times and the possibility for quantitative investigations of large areas and datasets with correlative microscopy. We demonstrate Simultaneous CLEM (SCLEM) analyzing cell-cell connections and membrane protrusions in whole uncoated colon adenocarcinoma cell line cells stained for actin and cortactin with AlexaFluor488. SCLEM imaging of coverglass-mounted tissue sections with both electron-dense and fluorescence staining is also shown.
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Affiliation(s)
- Nalan Liv
- Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - A. Christiaan Zonnevylle
- Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Angela C. Narvaez
- Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | | | - Philip W. Voorneveld
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Miriam S. Lucas
- Electron Microscopy ETH Zurich - EMEZ, ETH Zurich, Zurich, Switzerland
| | - James C. Hardwick
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Roger A. Wepf
- Electron Microscopy ETH Zurich - EMEZ, ETH Zurich, Zurich, Switzerland
| | - Pieter Kruit
- Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
| | - Jacob P. Hoogenboom
- Department of Imaging Science and Technology, Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands
- * E-mail:
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9
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Heijmans J, Muncan V, Jacobs RJ, de Jonge-Muller ESM, Graven L, Biemond I, Ederveen AG, Groothuis PG, Mosselman S, Hardwick JC, Hommes DW, van den Brink GR. Intestinal tumorigenesis is not affected by progesterone signaling in rodent models. PLoS One 2011; 6:e22620. [PMID: 21818351 PMCID: PMC3144908 DOI: 10.1371/journal.pone.0022620] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Accepted: 06/26/2011] [Indexed: 01/06/2023] Open
Abstract
Clinical data suggest that progestins have chemopreventive properties in the development of colorectal cancer. We set out to examine a potential protective effect of progestins and progesterone signaling on colon cancer development. In normal and neoplastic intestinal tissue, we found that the progesterone receptor (PR) is not expressed. Expression was confined to sporadic mesenchymal cells. To analyze the influence of systemic progesterone receptor signaling, we crossed mice that lacked the progesterone receptor (PRKO) to the ApcMin/+ mouse, a model for spontaneous intestinal polyposis. PRKO-ApcMin/+mice exhibited no change in polyp number, size or localization compared to ApcMin/+. To examine effects of progestins on the intestinal epithelium that are independent of the PR, we treated mice with MPA. We found no effects of either progesterone or MPA on gross intestinal morphology or epithelial proliferation. Also, in rats treated with MPA, injection with the carcinogen azoxymethane did not result in a difference in the number or size of aberrant crypt foci, a surrogate end-point for adenoma development. We conclude that expression of the progesterone receptor is limited to cells in the intestinal mesenchyme. We did not observe any effect of progesterone receptor signaling or of progestin treatment in rodent models of intestinal tumorigenesis.
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Affiliation(s)
- Jarom Heijmans
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
- Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
- * E-mail: (JH); (GRvdB)
| | - Vanesa Muncan
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
- Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
| | - Rutger J. Jacobs
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Laura Graven
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Izak Biemond
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Antwan G. Ederveen
- Merck, Sharpe and Dohme, Women's Health Department, Oss, The Netherlands
| | | | - Sietse Mosselman
- Merck, Sharpe and Dohme, Women's Health Department, Oss, The Netherlands
| | - James C. Hardwick
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Daniel W. Hommes
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Gijs R. van den Brink
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands
- Tytgat Institute for Liver and Intestinal Research, Academic Medical Center, Amsterdam, The Netherlands
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands
- * E-mail: (JH); (GRvdB)
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10
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van Dop WA, Heijmans J, Büller NVJA, Snoek SA, Rosekrans SL, Wassenberg EA, van den Bergh Weerman MA, Lanske B, Clarke AR, Winton DJ, Wijgerde M, Offerhaus GJ, Hommes DW, Hardwick JC, de Jonge WJ, Biemond I, van den Brink GR. Loss of Indian Hedgehog activates multiple aspects of a wound healing response in the mouse intestine. Gastroenterology 2010; 139:1665-76, 1676.e1-10. [PMID: 20682322 DOI: 10.1053/j.gastro.2010.07.045] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2009] [Revised: 07/09/2010] [Accepted: 07/19/2010] [Indexed: 12/22/2022]
Abstract
BACKGROUND & AIMS Indian Hedgehog (Ihh) is expressed by the differentiated epithelial cells of the small intestine and signals to the mesenchyme where it induces unidentified factors that negatively regulate intestinal epithelial precursor cell fate. Recently, genetic variants in the Hh pathway have been linked to the development of inflammatory bowel disease. METHODS We deleted Ihh from the small intestinal epithelium in adult mice using Cyp1a1-CreIhh(fl/fl) conditional Ihh mutant mice. Intestines were examined by immunohistochemistry, in situ hybridization, and real-time polymerase chain reaction. RESULTS Deletion of Ihh from the intestinal epithelium initially resulted in a proliferative response of the intestinal epithelium with lengthening and fissioning of crypts and increased Wnt signaling. The epithelial proliferative response was associated with loss of bone morphogenetic protein and Activin signaling from the epithelium of the villus and crypts, respectively. At the same stage we observed a substantial influx of fibroblasts and macrophages into the villus core with increased mesenchymal transforming growth factor-β signaling and deposition of extracellular matrix proteins. Prolonged loss of Ihh resulted in progressive leukocyte infiltration of the crypt area, blunting and loss of villi, and the development of intestinal fibrosis. CONCLUSIONS Loss of Ihh initiates several events that are characteristic of an intestinal wound repair response. Prolonged loss resulted in progressive inflammation, mucosal damage, and the development of intestinal fibrosis. Ihh is a signal derived from the superficial epithelial cells that may act as a critical indicator of epithelial integrity.
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Affiliation(s)
- Willemijn A van Dop
- Department of Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, The Netherlands.
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11
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van der Marel S, Duijvestein M, Hardwick JC, van den Brink GR, Veenendaal R, Hommes DW, Fidder HH. Quality of web-based information on inflammatory bowel diseases. Inflamm Bowel Dis 2009; 15:1891-6. [PMID: 19462423 DOI: 10.1002/ibd.20976] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2009] [Accepted: 03/25/2009] [Indexed: 12/12/2022]
Abstract
BACKGROUND The Internet is the largest source of health information and is widely used by inflammatory bowel disease (IBD) patients. As information is largely unregulated, our objective was to evaluate the quality, readability, accuracy, and accessibility of the information concerning IBD available on the World Wide Web. METHODS The phrases "inflammatory bowel disease," "Crohn's disease," and "Ulcerative Colitis" were entered separately as search terms into the 6 most commonly used search engines. Sites were categorized as institutional, pharmaceutical, nonpharmaceutical commercial sites, charitable, support, or alternative medicine. Websites were evaluated for content quality using the validated DISCERN rating instrument. Readability was graded by the Flesch Reading Ease and the Flesch-Kincaid Grade Level score. RESULTS Of the 76 websites evaluated by DISCERN, 43% of the sites were rated as excellent to good and 57% as fair to poor. Alternative medicine sites scored significant lower (P > 0.05) than institutional, pharmaceutical, and nonpharmaceutical commercial sites. There was no relation between a rating score and the position of a website on the search engine ranking. The median Flesch Reading Ease Score was 41.65 (range, 2.6-77.7) and 11.85 (range, 6.2-21.1) for the Flesch-Kincaid Grade Level. CONCLUSIONS The quality of websites containing information on IBD varies widely. Most of the online material available is too difficult to comprehend for a substantial portion of the patient population, and good quality information may be beyond reach of the average information seeker.
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Affiliation(s)
- Sander van der Marel
- Department of Gastroenterology & Hepatology, Leiden University Medical Center, Leiden, The Netherlands.
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12
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van Dop WA, Uhmann A, Wijgerde M, Sleddens-Linkels E, Heijmans J, Offerhaus GJ, van den Bergh Weerman MA, Boeckxstaens GE, Hommes DW, Hardwick JC, Hahn H, van den Brink GR. Depletion of the colonic epithelial precursor cell compartment upon conditional activation of the hedgehog pathway. Gastroenterology 2009; 136:2195-2203.e1-7. [PMID: 19272384 DOI: 10.1053/j.gastro.2009.02.068] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 02/11/2009] [Accepted: 02/19/2009] [Indexed: 12/23/2022]
Abstract
BACKGROUND & AIMS The intestinal epithelium is a homeostatic system in which differentiated cells are in dynamic equilibrium with rapidly cycling precursor cells. Wnt signaling regulates intestinal epithelial precursor cell fate and proliferation. Homeostatic systems exist by virtue of negative feedback loops, and we have previously identified the Hedgehog (Hh) pathway as a potential negative feedback signal in the colonic epithelium. Indian hedgehog (Ihh) is produced by the differentiated enterocytes and negatively regulates Wnt signaling in intestinal precursor cells. We studied the role of members of the Hh signaling family in the intestine using a conditional genetic approach. METHODS We inactivated the Hh receptor Patched1 (Ptch1) in adult mice, resulting in constitutive activation of the Hh signaling pathway. Effects on colonic mucosal homeostasis were examined. Colon tissues were examined by immunohistochemistry, in situ hybridization, transmission electron microscopy, and real-time polymerase chain reaction. RESULTS Ihh but not Sonic hedgehog (Shh) was expressed in colonic epithelium. Expression of Ptch1 and Gli1 was restricted to the mesenchyme. Constitutive activation of Hh signaling resulted in accumulation of myofibroblasts and colonic crypt hypoplasia. A reduction in the number of epithelial precursor cells was observed with premature development into the enterocyte lineage and inhibition of Wnt signaling. Activation of Hh signaling resulted in induction of the expression of bone morphogenetic proteins (Bmp) and increased Bmp signaling in the epithelium. CONCLUSIONS Hh signaling acts in a negative feedback loop from differentiated cells via the mesenchyme to the colonic epithelial precursor cell compartment in the adult mouse.
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Affiliation(s)
- Willemijn A van Dop
- Center for Experimental Molecular Medicine, Academic Medical Center, Amsterdam, The Netherlands.
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13
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Abstract
Much of the current understanding of colorectal cancer stems from the study of rare, inherited colorectal cancer syndromes. Mutations in the bone morphogenetic protein (BMP) pathway have been found in juvenile polyposis, an inherited polyposis syndrome that predisposes to colorectal cancer. The hamartomas that develop in these patients and in BMP pathway mutant mice have a remarkable mesenchymal component. Further evidence in mice suggests a primary role for mesenchymal loss of BMP signalling in hamartoma development. Here, we examine this evidence and question its relevance to sporadic colorectal carcinogenesis.
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Affiliation(s)
- James C Hardwick
- Department of Gastroenterology & Hepatology, Leiden University Medical Center, Leiden, the Netherlands.
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14
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Bleuming SA, He XC, Kodach LL, Hardwick JC, Koopman FA, Ten Kate FJ, van Deventer SJH, Hommes DW, Peppelenbosch MP, Offerhaus GJ, Li L, van den Brink GR. Bone morphogenetic protein signaling suppresses tumorigenesis at gastric epithelial transition zones in mice. Cancer Res 2007; 67:8149-55. [PMID: 17804727 DOI: 10.1158/0008-5472.can-06-4659] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Bone morphogenetic protein (BMP) signaling is known to suppress oncogenesis in the small and large intestine of mice and humans. We examined the role of Bmpr1a signaling in the stomach. On conditional inactivation of Bmpr1a, mice developed neoplastic lesions specifically in the squamocolumnar and gastrointestinal transition zones. We hypothesized that the regulation of epithelial cell fate may be less well defined in these junctional zones than in the adjacent epithelium and found that the mucosa at the squamocolumnar junction in mice shows a lack of differentiated fundic gland cell types and that foveolar cells at the gastrointestinal junctional zone lack expression of the foveolar cell marker Muc5ac. Precursor cell proliferation in both transition zones was higher than in the surrounding epithelium. Our data show that BMP signaling through Bmpr1a suppresses tumorigenesis at gastric epithelial junctional zones that are distinct from the adjacent gastric epithelium in both cellular differentiation and proliferation.
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Affiliation(s)
- Sylvia A Bleuming
- Center for Experimental and Molecular Medicine, Academic Medical Center, Amsterdam, The Netherlands
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15
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Dekker E, van den Broek FJ, Reitsma JB, Hardwick JC, Offerhaus GJ, van Deventer SJ, Hommes DW, Fockens P. Narrow-band imaging compared with conventional colonoscopy for the detection of dysplasia in patients with longstanding ulcerative colitis. Endoscopy 2007; 39:216-21. [PMID: 17385106 DOI: 10.1055/s-2007-966214] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND AND STUDY AIM Patients with longstanding ulcerative colitis are at increased risk of developing colorectal cancer. Colonoscopic surveillance is advised, but the detection of neoplasia by conventional colonoscopy is difficult. The aim of this study was to compare the accuracy of narrow-band imaging (NBI), a new imaging technique, with standard colonoscopy for the detection of neoplasia in patients with longstanding ulcerative colitis. PATIENTS AND METHODS This was a prospective, randomized, crossover study of 42 patients with longstanding ulcerative colitis. All participants underwent NBI and conventional colonoscopy with at least 3 weeks between the procedures. Randomization determined the order of the examinations. Targeted biopsies were taken during both procedures; additional random biopsies were taken at conventional colonoscopy only. The number of patients with neoplasia detected by targeted biopsies was used to assess the sensitivity for each technique. RESULTS With NBI, 52 suspicious lesions were detected in 17 patients, compared with 28 suspicious lesions in 13 patients detected during conventional colonoscopy. Histopathological evaluation of targeted biopsies revealed 11 patients with neoplasia: in four patients the neoplasia was detected by both techniques, in four patients neoplasia was detected only by NBI, and in three patients neoplasia was detected only by conventional colonoscopy ( P = 0.705). Aside from targeted biopsies, 1522 random biopsies were taken. These revealed one additional patient with dysplasia that was not detected by either technique. CONCLUSIONS The sensitivity of the studied first-generation NBI system for the detection of patients with neoplasia seems to be comparable to conventional colonoscopy, although more suspicious lesions were found during NBI. We believe that it is still too early to stop taking additional random biopsies at surveillance colonoscopy in patients with ulcerative colitis.
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Affiliation(s)
- E Dekker
- Department of Gastroenterology and Hepatology, Academic Medical Center, Amsterdam, The Netherlands.
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16
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Bleuming SA, Kodach LL, Garcia Leon MJ, Richel DJ, Peppelenbosch MP, Reitsma PH, Hardwick JC, van den Brink GR. Altered bone morphogenetic protein signalling in the Helicobacter pylori-infected stomach. J Pathol 2006; 209:190-7. [PMID: 16550632 DOI: 10.1002/path.1976] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Morphogens regulate epithelial cell fate decisions in the adult gastrointestinal tract. The authors hypothesized that influx of inflammatory cells into the lamina propria may disturb the normal expression gradients of morphogens (morphogenetic landscape) in gastrointestinal epithelia. Changes in the activity of the bone morphogenetic protein (BMP) pathway in normal and Helicobacter pylori-infected gastric mucosa were therefore examined. It is shown that BMP receptors, the activated (phosphorylated) form of the intracellular BMP signal transduction protein SMAD1, and BMP target ID2 all localize to gastric epithelial cells that are at the end of the axis of epithelial renewal in normal mucosa. Colonization of human gastric mucosa with H. pylori was associated with an increase in BMP2 expression due to influx of inflammatory cells that produce BMP2. Furthermore, whereas no BMP4 was detected in the normal antrum, focal infiltrates of BMP4-expressing cells were found in the H. pylori-infected stomach. This influx of BMP-expressing cells was associated with an increase in epithelial BMP signalling. Interestingly, a shift in activity of the BMP pathway was observed towards the precursor cell compartment (isthmus) of the gastric units. Thus, H. pylori infection results in an influx of inflammatory cells that disturb the normal activity gradient of a morphogenetic pathway with an established role in epithelial cell fate regulation. The data suggest that morphological changes in epithelial histology may result from alterations in the morphogenetic landscape secondary to changes in the cellular composition of the lamina propria.
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Affiliation(s)
- S A Bleuming
- Department of Experimental Internal Medicine, Academic Medical Center, Amsterdam, The Netherlands, and Department of Gastroenterology and Hepatology, Geneva University Hospital, Switzerland
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17
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Diks SH, Hardwick JC, Diab RM, van Santen MM, Versteeg HH, van Deventer SJH, Richel DJ, Peppelenbosch MP. Activation of the canonical beta-catenin pathway by histamine. J Biol Chem 2003; 278:52491-6. [PMID: 14563838 DOI: 10.1074/jbc.m310712200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Histamine signaling is a principal regulator in a variety of pathophysiological processes including inflammation, gastric acid secretion, neurotransmission, and tumor growth. We report that histamine stimulation causes transactivation of a T cell factor/beta-catenin-responsive construct in HeLa cells and in the SW-480 colon cell line, whereas histamine did not effect transactivation of a construct containing the mutated response construct FOP. On the protein level, histamine treatment increases phosphorylation of glycogen synthase kinase 3-beta in HeLa cells, murine macrophages, and DLD-1, HT-29, and SW-480 colon cell lines. Furthermore, histamine also decreases the phosphorylated beta-catenin content in HeLa cells and murine macrophages. Finally, pharmacological inhibitors of the histamine H1 receptor counteracted histamine-induced T cell factor/beta-catenin-responsive construct transactivation and the dephosphorylation of beta-catenin in HeLa cells and in macrophages. We conclude that the canonical beta-catenin pathway acts downstream of the histamine receptor H1 in a variety of cell types. The observation that inflammatory molecules, like histamine, activate the beta-catenin pathway may provide a molecular explanation for a possible link between inflammation and cancer.
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Affiliation(s)
- Sander H Diks
- Laboratory for Experimental Internal Medicine, Academic Medical Center, Meibergdreef 9, The Netherlands.
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18
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van den Brink GR, Hardwick JC, Tytgat GN, Brink MA, Ten Kate FJ, Van Deventer SJ, Peppelenbosch MP. Sonic hedgehog regulates gastric gland morphogenesis in man and mouse. Gastroenterology 2001; 121:317-28. [PMID: 11487541 DOI: 10.1053/gast.2001.26261] [Citation(s) in RCA: 202] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
BACKGROUND & AIMS Gastric epithelial renewal is an asymmetric process. A stem cell located halfway up the tubular unit gives rise to both a basal gland region and a luminal pit compartment, but the mechanisms responsible for the maintenance of this asymmetry are obscure. We investigated whether Sonic hedgehog (Shh), an established polarizing signal protein during development, is expressed and functional in the adult human and murine stomach. METHODS Expression of Shh and putative transcriptional targets was investigated using immunoblot and immunohistochemistry. Mice were treated with the Shh inhibitor cyclopamine and examined for expression levels of Shh targets and proliferation of gastric epithelial cells. RESULTS Shh was expressed in the stomach. In cyclopamine-treated mice, we observed decreased expression of HNF3beta, Islet (Isl)-1 and BMP4, 3 putative Shh target genes. Inhibition of Shh markedly enhanced gastric epithelial proliferation and affected the cell cycle of gastric epithelial gland cells, whereas pit cells remained unaffected. CONCLUSIONS Shh controls the expression of at least 3 factors important for epithelial differentiation and is a negative regulator of gastric gland cell proliferation. Shh is a candidate polarizing signal in the maintenance of gastric pit-gland asymmetry.
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Affiliation(s)
- G R van den Brink
- Department of Experimental Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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19
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Abstract
BACKGROUND AND AIMS Obesity increases the risk of colon cancer, whereas physical activity reduces the risk. Plasma levels of leptin increase in proportion to the level of obesity and are reduced by physical activity. Leptin acts as a growth factor for several cell types and thus may provide a biological explanation for the observed epidemiological risk factors. The aim of this study was to investigate whether leptin is a growth factor for colonic epithelial cells. METHODS The presence of the leptin receptor in human colon cancer cell lines was assessed using reverse-transcription polymerase chain reaction and immunoblotting, and its presence in human colonic tissue was assessed by immunohistochemistry. The effects of leptin in vitro on HT29 cells were assessed by assessing p42/44 mitogen-activated protein kinase phosphorylation, thymidine incorporation, and cell numbers and in vivo in C57BL/6 mice by colonic bromodeoxyuridine incorporation. RESULTS The leptin receptor is expressed in human colon cancer cell lines and human colonic tissue. Stimulation with leptin leads to phosphorylation of p42/44 mitogen-activated protein kinase and increases proliferation in vitro and in vivo. CONCLUSIONS Leptin is a growth factor in colonic epithelial cells and one that may provide a biological explanation for the observed associations between obesity, physical activity, and colon cancer.
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Affiliation(s)
- J C Hardwick
- Department of Experimental Internal Medicine, Academic Medical Center, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
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20
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Hardwick JC, Duthie SJ. Can cardiotocography prior to induction of labour predict obstetric intervention? A pilot study. J OBSTET GYNAECOL 2001; 21:258-60. [PMID: 12521855 DOI: 10.1080/01443610120046369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
We set out to study the value of cardiotocography (CTG) performed before induction of labour for prolonged pregnancy in predicting obstetric intervention. This was a prospective observational study, based in a district general hospital. We studied 100 consecutive patients who underwent induction of labour for prolonged pregnancy. Cardiotocographs (CTGs) were performed before induction of labour on the tenth day after the estimated date of confinement (290 days). The CTGs were then reviewed without knowledge of the outcome of the induction of labour. Obstetric outcomes were then compared. The main outcome measures were the intrapartum presence or absence of meconium stained liquor and the necessity for obstetric intervention. Ninety per cent of CTGs were normal. There was no difference found between the two groups for operative delivery or the presence of meconium liquor. Caesarean section was more likely in the group with an abnormal CTG before induction of labour, but the possibility of this being due to chance is high in this study. There was one case of undiagnosed growth restriction in the abnormal CTG group. These results may be due to a true lack of difference in obstetric intervention between women with normal or abnormal CTGs prior to induction of labour or more probably an inability to detect a difference in our small study. These baseline data allow the calculations necessary for a more substantive trial.
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21
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Parsons RL, Rossignol TM, Calupca MA, Hardwick JC, Brass KM. PACAP peptides modulate guinea pig cardiac neuron membrane excitability and neuropeptide expression. Ann N Y Acad Sci 2001; 921:202-10. [PMID: 11193824 DOI: 10.1111/j.1749-6632.2000.tb06967.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Morphological studies identified PACAP-immunoreactive nerve fibers in dense pericellular arrangements around virtually every cholinergic parasympathetic neuron of guinea pig cardiac ganglia; all postganglionic cardiac neurons expressed membrane-associated PAC1 receptor protein. Characterization of the alternative splice variants established predominant expression of the PAC1(very short) receptor transcript containing neither HIP nor HOP exons. PACAP depolarized cardiac neurons and increased membrane excitability; the excitability resulted from neither altered action potential properties nor inhibition of IM. Treatment of cardiac ganglia explants with PACAP significantly reduced the numbers of cholinergic neurons coexpressing somatostatin immunoreactivity, which did not appear to be correlated with prosomatostatin mRNA expression. The PACAP-mediated decrease in somatostatin immunoreactive neurons required calcium influx through L-type calcium channels and activation of adenylyl cyclase, whereas activation of phospholipase C or protein kinase A was not required. These observations indicate that PACAP through the PAC1 receptors elicits complex actions on guinea pig parasympathetic cardiac ganglia neurons, including modulation of membrane ion conductances and modulation of neuropeptide expression.
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Affiliation(s)
- R L Parsons
- Department of Anatomy and Neurobiology, University of Vermont College of Medicine, Burlington, Vermont 05405, USA.
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22
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Abstract
The potential interaction between the immune system and the autonomic nervous system was examined in the cardiac ganglia of guinea pigs. Intracellular voltage recordings were used to determine the effects of mast cell degranulation on the membrane properties of parasympathetic neurons in animals actively sensitized to ovalbumin. Stimulation of mast cell degranulation by perfusion with ovalbumin (10 micrograms/ml) produced a depolarization and increase in the excitability of intracardiac neurons. These effects could be mimicked by histamine application, either by perfusion (10 microM) or by local pressure application (100 microM, 1-2 s application). In either case, histamine application resulted in a similar membrane depolarization and increase in excitability. Immunohistochemical experiments demonstrated that histamine-immunoreactive mast cells are located in close proximity to parasympathetic postganglionic neurons. The histamine response was not due to release of other neurotransmitters from adjacent nerve terminals and both the depolarization and increase in excitability were inhibited by the H1 antagonist, pyrilamine (300 nM), and were unaffected by the H2 antagonist cimetidine (5 microM). Incubation of cardiac ganglion preparations from sensitized animals with pyrilamine prior to ovalbumin perfusion resulted in the inhibition of both the depolarization and increase in excitability. These results demonstrate that mast cell degranulation, and the subsequent release of histamine, results in the stimulation of intracardiac neurons via the activation of H1 receptors. Thus, local inflammatory reactions in the cardiac tissue can lead to the rapid activation of parasympathetic neurons, thereby altering cardiac function.
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Affiliation(s)
- M J Powers
- Department of Biology, Ithaca College, Ithaca, NY 14850, USA
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23
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Hardwick JC, van den Brink GR, Offerhaus GJ, van Deventer SJ, Peppelenbosch MP. NF-kappaB, p38 MAPK and JNK are highly expressed and active in the stroma of human colonic adenomatous polyps. Oncogene 2001; 20:819-27. [PMID: 11314016 DOI: 10.1038/sj.onc.1204162] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2000] [Revised: 11/30/2000] [Accepted: 12/05/2000] [Indexed: 12/11/2022]
Abstract
The factors that govern the progression from colonic adenomatous polyp to colon cancer are poorly understood. The observation that NSAIDs act as chemopreventative agents and reduce the size of colonic polyps suggests the involvement of inflammatory signalling, but inflammatory signalling in colonic polyps has not been studied. We investigated the expression of the active forms of NF-kappaB, JNK and p38 MAPK using immunohistochemistry with activation specific antibodies in human colonic adenomas. We show that active NF-kappaB is seen in stromal macrophages that also express COX-2 and TNF-alpha, active JNK is seen in stromal and intraepithelial T-lymphocytes and periendothelial cells of new blood vessels, and active p38 MAPK is most highly expressed in macrophages and other stromal cells. These results demonstrate the presence of active inflammatory signal transduction in colonic polyps and that these are predominantly in the stroma. In the case of NF-kappaB this coincides with the cellular localisation of COX-2. These results support evidence that NSAIDs may act through effects on stromal cells rather than epithelial cells.
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Affiliation(s)
- J C Hardwick
- Department of Experimental Internal Medicine, Academic Medical Center, Amsterdam, The Netherlands
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25
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Hardwick JC. Outpatient hysteroscopy versus day case hysteroscopy. Larger and more robust studies are needed. BMJ 2001; 322:47-8. [PMID: 11141165 PMCID: PMC1119314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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26
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Abstract
The presence and potential origin of the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) was determined in cardiac ganglia of the mudpuppy, Necturus maculosus. Although PACAP has been implicated in the regulation of cardiac function in several mammalian species, the presence of this peptide in the autonomic nervous system (ANS) of other species is unclear. Thus, this study is the first to characterize this highly conserved peptide in the ANS of a non-mammalian species. PACAP-immunoreactivity was observed in nerve fibers throughout the mudpuppy cardiac ganglia and often was co-localized with the sensory neuropeptides substance P and calcitonin gene-related peptide. Removal of all extrinsic inputs to the ganglia by organ culture eliminated PACAP-immunoreactivity in the cardiac ganglia, whereas bilateral vagotomies only partially reduced PACAP-labeling. PACAP-immunoreactive neurons were observed in both high thoracic dorsal root ganglia and in vagal sensory ganglia. While no PACAP-positive neurons were observed in caudal medulla brainstem regions, PACAP-containing nerve fibers were found in the region of the nucleus solitarius. These results suggest that, in the mudpuppy, PACAP is found primarily in visceral afferent fibers, originating from cells in either the dorsal root ganglia or vagal sensory ganglia. Based on their anatomic localization, these afferent fibers may function to transmit important sensory information to cardiovascular centers in the brain as well as serving as local reflex inputs to modulate postganglionic parasympathetic output within the cardiac ganglion itself.
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Affiliation(s)
- L K Schoenfeld
- Neuroscience Department, Case Western Reserve University, Cleveland, OH 44106, USA
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27
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van den Brink GR, O'Toole T, Hardwick JC, van den Boogaardt DE, Versteeg HH, van Deventer SJ, Peppelenbosch MP. Leptin signaling in human peripheral blood mononuclear cells, activation of p38 and p42/44 mitogen-activated protein (MAP) kinase and p70 S6 kinase. Mol Cell Biol Res Commun 2000; 4:144-50. [PMID: 11281728 DOI: 10.1006/mcbr.2001.0270] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The adipocyte-derived hormone leptin plays an important role as a relayer of nutritional status to several organ systems. Evidence is accumulating that leptin plays an important role in the adequate functioning and maintenance of the immune system. Here we show that leptin induces sustained phosphorylation of p38 MAP kinase in human peripheral blood mononuclear cells (PBMCs). We show furthermore that leptin induces two routes to phosphorylation of the 40S ribosomal protein S6, one is activation of the p90 ribosomal S6 kinase (RSK) via the MEK/p42/p44 MAP kinase pathway, the other is via activation of p70 S6 kinase. Thus, these results give new insight in the mechanism that underlies the immunomodulatory effects of leptin.
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Affiliation(s)
- G R van den Brink
- Department of Experimental Internal Medicine, Academic Medical Center, Amsterdam, The Netherlands
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28
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Calupca MA, Hendricks GM, Hardwick JC, Parsons RL. Role of mitochondrial dysfunction in the Ca2+-induced decline of transmitter release at K+-depolarized motor neuron terminals. J Neurophysiol 1999; 81:498-506. [PMID: 10036254 DOI: 10.1152/jn.1999.81.2.498] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The present study tested whether a Ca2+-induced disruption of mitochondrial function was responsible for the decline in miniature endplate current (MEPC) frequency that occurs with nerve-muscle preparations maintained in a 35 mM potassium propionate (35 mM KP) solution containing elevated calcium. When the 35 mM KP contained control Ca2+ (1 mM), the MEPC frequency increased and remained elevated for many hours, and the mitochondria within twitch motor neuron terminals were similar in appearance to those in unstimulated terminals. All nerve terminals accumulated FM1-43 when the dye was present for the final 6 min of a 300-min exposure to 35 mM KP with control Ca2+. In contrast, when Ca2+ was increased to 3.6 mM in the 35 mM KP solution, the MEPC frequency initially reached frequencies >350 s-1 but then gradually fell approaching frequencies <50 s-1. A progressive swelling and eventual distortion of mitochondria within the twitch motor neuron terminals occurred during prolonged exposure to 35 mM KP with elevated Ca2+. After approximately 300 min in 35 mM KP with elevated Ca2+, only 58% of the twitch terminals accumulated FM1-43. The decline in MEPC frequency in 35 mM KP with elevated Ca2+ was less when 15 mM glucose was present or when preparations were pretreated with 10 microM oligomycin and then bathed in the 35 mM KP with glucose. When glucose was present, with or without oligomycin pretreatment, a greater percentage of twitch terminals accumulated FM1-43. However, the mitochondria in these preparations were still greatly swollen and distorted. We propose that prolonged depolarization of twitch motor neuron terminals by 35 mM KP with elevated Ca2+ produced a Ca2+-induced decrease in mitochondrial ATP production. Under these conditions, the cytosolic ATP/ADP ratio was decreased thereby compromising both transmitter release and refilling of recycled synaptic vesicles. The addition of glucose stimulated glycolysis which contributed to the maintenance of required ATP levels.
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Affiliation(s)
- M A Calupca
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington, Vermont 05405, USA
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29
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Hardwick JC, Best FA, Igwe F. A dilated cervical crypt as a cause of uterine enlargement. J OBSTET GYNAECOL 1999; 19:96-7. [PMID: 15512242 DOI: 10.1080/01443619966164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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May V, Beaudet MM, Parsons RL, Hardwick JC, Gauthier EA, Durda JP, Braas KM. Mechanisms of pituitary adenylate cyclase activating polypeptide (PACAP)-induced depolarization of sympathetic superior cervical ganglion (SCG) neurons. Ann N Y Acad Sci 1998; 865:164-75. [PMID: 9928009 DOI: 10.1111/j.1749-6632.1998.tb11175.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Our understanding of PACAP expression and regulation of sympathetic neuronal function has been augmented considerably over the last few years. Among the three major VIP/PACAP receptor subtypes, the SCG appears to express preferentially one particular variant of the PACAP-selective PACAP1 receptor coupled to multiple intracellular signaling cascades. The in situ histochemical hybridization and immunocytochemical studies of PACAP1 receptor mRNA and protein are in good agreement; nearly all of the SCG neurons express the PACAP-selective receptor, suggesting that most of the sympathetic neurons are under PACAP neuromodulation. In accord with that possibility, several independent studies have now demonstrated PACAP peptide expression in the IML sympathetic preganglionic neurons and fibers, including those projecting to the SCG, further emphasizing the significance of PACAP peptides as a preganglionic noncholinergic mediator of sympathetic function. Given the high potency of PACAP on any of a number of cellular responses, the functional relevance of PACAP peptides on SCG neurons is considerable. We have previously demonstrated the potency and efficacy of both PACAP27 and PACAP38 on sympathetic neuron neurotransmitter/neuropeptide production and secretion; the ability of these peptides to stimulate neuronal second messenger activation was also in the nanomolar range. These results are congruous with our current electrophysiological studies, which were driven to further define the dynamic sympathetic responses to PACAP. In line with the morphological studies, for example, more than 90% of the sympathetic neurons responded to PACAP. In agreement with previous neuropharmacological data, the PACAP-induced depolarizations were elicited at physiologically relevant peptide concentrations at high affinity PACAP-selective receptors. The effects were direct and the alterations in postganglionic neuronal membrane properties appeared to be mediated by several ionic mechanisms. If these studies were analogous to pieces in a puzzle to understand the effects of PACAP in sympathetic development and function, the picture of late has been more completely assembled. But several important challenges still remain. What are the signal transduction mechanisms that mediate the PACAP-induced changes in sympathetic membrane properties? How do the resulting alterations impact the acute and more long-term responses of sympathetic neurons? Does the coupling of PACAP1 receptors to intracellular signaling pathways differ during development, resulting in a transition from the neurotrophic properties of PACAP in neuroblasts to neuromodulatory roles of the peptides in postmitotic neurons? By looking at these issues in one distinct neuronal system, we enlarge our understanding and appreciation of peptides, and PACAP in particular, in the molecular and cellular events guiding neuronal development, function, and plasticity.
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Affiliation(s)
- V May
- Department of Anatomy and Neurobiology, University of Vermont College of Medicine, Given Health Science Center, Burlington 05405, USA
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Braas KM, May V, Harakall SA, Hardwick JC, Parsons RL. Pituitary adenylate cyclase-activating polypeptide expression and modulation of neuronal excitability in guinea pig cardiac ganglia. J Neurosci 1998; 18:9766-79. [PMID: 9822736 PMCID: PMC6793321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
Abstract
Cardiac output is regulated by the coordinate interactions of stimulatory sympathetic and inhibitory parasympathetic signals. Intracardiac parasympathetic ganglia are integrative centers of cardiac regulation, and modulation of the parasympathetic drive on the heart is accomplished by altering intrinsic cardiac ganglion neuron excitability. The pituitary adenylate cyclase-activating polypeptide (PACAP)/vasoactive intestinal peptide (VIP) family of peptides modulates cardiac function, and in guinea pig heart, PACAP appears to act directly on intrinsic parasympathetic cardiac ganglia neurons through PACAP-selective receptors. A multidisciplinary project tested whether cardiac PACAP peptides act through PACAP-selective receptors as excitatory neuromodulators amplifying the parasympathetic inhibition from guinea pig cardiac ganglia. The in vivo sources of regulatory PACAP peptides were localized immunocytochemically to neuronal fibers and a subpopulation of intrinsic postganglionic cardiac neurons. RT-PCR confirmed that cardiac ganglia expressed proPACAP transcripts and have PACAP peptide biosynthetic capabilities. Messenger RNA encoding PACAP-selective PAC1 receptor isoforms were also present in cardiac ganglia. Alternative splicing of PAC1 receptor transcripts produced predominant expression of the very short variant with neither HIP nor HOP cassettes; lower levels of the PAC1HOP2 receptor mRNA were present. Almost all of the parasympathetic neurons expressed membrane-associated PAC1 receptor proteins, localized immunocytochemically, which correlated with the population of cells that responded physiologically to PACAP peptides. PACAP depolarized cardiac ganglia neurons and increased neuronal membrane excitability. The rank order of peptide potency on membrane excitability in response to depolarizing currents was PACAP27>PACAP38>VIP. The PACAP-induced increase in excitability was not a function of membrane depolarization nor was it caused by alterations in action potential configuration. These results support roles for PACAP peptides as integrative modulators amplifying, through PACAP-selective receptors, the parasympathetic cardiac ganglia inhibition of cardiac output.
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Affiliation(s)
- K M Braas
- Department of Anatomy and Neurobiology, The University of Vermont, College of Medicine, Burlington, Vermont 05405, USA
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Kennedy AL, Harakall SA, Lynch SW, Braas KM, Hardwick JC, Mawe GM, Parsons RL. Expression and physiological actions of neuropeptide Y in guinea pig parasympathetic cardiac ganglia. J Auton Nerv Syst 1998; 71:190-5. [PMID: 9760056 DOI: 10.1016/s0165-1838(98)00072-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Guinea pig atrial whole mount preparations containing the parasympathetic cardiac ganglia were used to establish the expression, distribution and actions of neuropeptide Y (NPY) in atrial tissues. NPY-immunoreactive fibers densely innervated the atrial myocardium and blood vessels. Fibers containing NPY also innervated intrinsic parasympathetic cardiac neurons. Four percent of the cardiac neurons, identified using microtubule associated protein-2 antiserum, were NPY-positive. An endogenous source of NPY was confirmed with reverse transcription PCR which demonstrated the presence of proNPY mRNA. Sixty percent of the parasympathetic cardiac neurons were hyperpolarized by local application of NPY. NPY also decreased the amplitude and duration of the action potential after hyperpolarization in 60% of the neurons and decreased the fast excitatory postsynaptic potential in about 50% of the cells. These observations indicate that NPY is anatomically positioned to directly alter the output of the parasympathetic cardiac ganglia either by hyperpolarizing the cardiac neurons or by decreasing the fast synaptic input which drives individual neurons.
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Affiliation(s)
- A L Kennedy
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405, USA
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Hardwick JC, Mawe GM, Parsons RL. Tachykinin-induced activation of non-specific cation conductance via NK3 neurokinin receptors in guinea-pig intracardiac neurones. J Physiol 1997; 504 ( Pt 1):65-74. [PMID: 9350618 PMCID: PMC1159936 DOI: 10.1111/j.1469-7793.1997.065bf.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
1. Whole mount preparations from guinea-pig hearts were used to characterize the receptors and ionic mechanisms mediating the substance P (SP)-induced depolarization of parasympathetic postganglionic neurones of the cardiac ganglion. 2. Measurement of the amplitude of depolarization in response to superfusion of different tachykinin agonists (neurokinins A (NKA) and B (NKB), SP, and senktide) gave a rank-order potency of NKB = senktide > NKA > SP, indicating involvement of an NK3 receptor. The use of the selective tachykinin receptor antagonists SR 140333, SR 48986, and SR 142801 demonstrated that only the NK3 receptor antagonist SR 142801 inhibited the SP-induced depolarization. 3. The SP-induced depolarization was not inhibited by Ba2+, TEA, or niflumic acid, or altered by reduced Cl- solutions, but was attenuated in reduced Na+ solutions. Single electrode voltage clamp studies demonstrated that the SP-induced inward current increased in amplitude at more negative potentials, had a reversal potential of approximately 0 mV, and was reduced in amplitude in reduced Na+ solutions. 4. We conclude that the SP-induced depolarization in guinea-pig postganglionic parasympathetic neurones of the cardiac ganglion is due to NK3-mediated activation of a non-selective cation conductance.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, University of Vermont, Burlington 05405, USA
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Connor EA, Dunaevsky A, Griffiths DJ, Hardwick JC, Parsons RL. Transmitter release differs at snake twitch and tonic endplates during potassium-induced nerve terminal depolarization. J Neurophysiol 1997; 77:749-60. [PMID: 9065847 DOI: 10.1152/jn.1997.77.2.749] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Twitch and tonic muscle fibers of snake skeletal muscle differ in their synpatic as well as mechanical properties. These experiments were aimed at detemining the basis of the difference in vesicular release properties of nerve terminals at twitch and tonic endplates. Miniature endplate currents (MEPCs) were recorded from voltage-clamped garter snake muscle fibers depolarized by high K+ in either a control Ca2+ or high-Ca2+ solution. MEPC frequency increased at twitch and tonic endplates and remained elevated for 8 h during depolarization in control Ca2+. At twitch endplates depolarized in the presence of high Ca2+, an increase in MEPC frequency was followed by a progressive decline. In contrast, MEPC frequency remained elevated in high Ca2+ at tonic endplates. The observed decrease in MEPC frequency at depolarized twitch endplates in high Ca2+ was not a function of the level of depolarization or initial MEPC frequency, nor was it due to a reduction in MEPC amplitude and loss of MEPCs in baseline noise. An optical assay of presynaptic function in which the activity-dependent dye FM1-43 was used confirmed that quantal releases differs at twitch and tonic endplates. Most twitch nerve terminals were labeled by FM1-43 during prolonged depolarization with control Ca2+ or after brief depolarization with high Ca2+. In contrast, the number of twitch nerve terminals and the degree to which they were stained was greatly reduced after prolonged exposure to high K+ and high Ca2+, whereas depolarized tonic endplates were well stained by FM1-43 during brief and prolonged exposure to high Ca2+. FM1-43 staining also revealed variable levels of quantal release between individual boutons at twitch endplates after prolonged depolarization in high-Ca2+ solution. The observed reduction in presynaptic function at twitch nerve terminals after prolonged depolarization in high-Ca2+ solution was reversible and therefore not due to irreversible damage to terminal boutons. MEPC frequency increased at both twitch and tonic endplates when either Sr2+ or Ba2+ was substituted for high Ca2+ during K(+)-induced depolarization. Over time, in Sr2+ or Ba2+ solutions, MEPC frequency remained elevated at tonic endplates but declined at twitch endplates with a time course similar to that observed in high Ca2+. MEPC amplitudes at both endplates remained constant. We conclude that the regulation of quantal release differs in nerve terminals innervating twitch and tonic endplates and postulate that differential intraterminal accumulation of Ca2+ may underlie the observed difference in presynaptic function.
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Affiliation(s)
- E A Connor
- Department of Biology, University of Massachusetts, Amherst 01003, USA
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Hardwick JC, Parsons RL. Activation of the protein phosphatase calcineurin during carbachol exposure decreases the extent of recovery from end-plate desensitization. J Neurophysiol 1996; 76:3609-16. [PMID: 8985861 DOI: 10.1152/jn.1996.76.6.3609] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
1. Our previous studies demonstrated that protein kinase C (PKC) activity is required for acetylcholine (ACh) sensitivity to recover fully at snake twitch fiber end plates after prolonged exposure to carbachol. In the present studies, we have investigated whether protein phosphatase(s), activated during carbachol exposure, dephosphorylated critical membrane proteins, which required rephosphorylation by PKC to maintain end-plate sensitivity. End-plate sensitivity was assessed from measurements of miniature end-plate currents (MEPCs) and carbachol-activated currents (EPCCARBS). Conductance of ACh-activated channels was determined from patch-clamp recordings of single-channel currents. 2. Pretreatment of snake muscle preparations with the protein kinase inhibitor staurosporine (0.5 microM), followed by a 10-min exposure to 540 microM carbachol, reduced mean MEPC amplitudes to values 30-40% less than those recorded before carbachol exposure. Conversely, at control end plates exposed to carbachol, the mean MEPC amplitude was reduced by only approximately 5% compared with precarbachol values. This staurosporine-induced decrease in ACh sensitivity could be prevented by pretreatment with the protein phosphatase 2B (calcineurin) inhibitor deltamethrin (0.5 microM), whereas okadaic acid (5 microM) and calyculin A (0.5 microM), inhibitors of protein phosphatases 1 and 2A, had no effect. 3. After a 10-min exposure to 540 microM carbachol, EPCCARB amplitudes (produced by local superfusion with 20 microM carbachol) were significantly smaller at staurosporine-treated end plates than at control end plates. In contrast, the EPCCARB amplitude recorded from end plates pretreated with both deltamethrin and staurosporine was not significantly different from that recorded at control end plates. 4. Substitution of 10 mM Mn2+ for external Ca2+ during the exposure to 540 microM carbachol prevented the decrease in MEPC amplitude recovery at staurosporine-treated end plates. These results suggested that the alteration in sensitivity at staurosporine-treated end plates was calcium dependent. 5. At control end plates, a single population of ACh-activated channels (45-50 pS) is observed both before and after a 10-min exposure to 540 microM carbachol. Conversely, at staurosporine-treated end plates, after exposure to carbachol, a second population of small-conductance (25-30 pS) ACh-activated channels is present in addition to the predominant 45- to 50-pS ACh-activated channels. In preparations pretreated with both deltamethrin and staurosporine, after carbachol exposure, there was a significant decrease in the frequency of small-conductance ACh-activated channels. Deltamethrin treatment alone produced no small-conductance channels before or after a 10-min exposure to 540 microM carbachol. Also, no small-conductance ACh-gated channels were recorded at PKC-inhibited end plates after carbachol exposure either with pretreatment with 10 microM cyclosporin A (another inhibitor of calcineurin) or with the substitution of 10 mM Mn2+ for Ca2+ during the 10-min agonist exposure. 6. We propose that during prolonged exposure to the nicotinic agonist carbachol, calcium influx through ACh-gated channels elevates the level of ionized calcium at the inner surface of the post-junctional membrane and that this local rise in intracellular calcium activates the calcium-dependent phosphatase calcineurin. Dephosphorylation of some key membrane protein by calcineurin leads to a decrease in the extent of recovery from desensitization. Under normal conditions, this process is effectively reversed by PKC activity and end-plate sensitivity recovers fully. However, when PKC is inhibited, the extent of recovery of end-plate sensitivity is decreased, and associated with this decrease is the presence of small-conductance ACh-activated channels not normally recorded at snake twitch fiber end plates.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, University of Vermont, Burlington 05405, USA
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Hardwick JC, Mawe GM, Parsons RL. Evidence for afferent fiber innervation of parasympathetic neurons of the guinea-pig cardiac ganglion. J Auton Nerv Syst 1995; 53:166-74. [PMID: 7560753 DOI: 10.1016/0165-1838(94)00182-j] [Citation(s) in RCA: 77] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The present study was done to establish whether peptidergic afferent inputs can modulate parasympathetic neurons of the guinea-pig cardiac ganglion. Whole mount preparations from the guinea-pig heart were utilized to localize afferent terminals by immunohistochemistry and for intracellular recordings from individual neurons in situ. Action potentials could be elicited by both intracellular current injection and stimulation of interganglionic fiber bundles. Two types of neuron, phasic (95%) and tonic (5%) as defined by their firing properties, were observed. High frequency (5-10 Hz) interganglionic fiber stimulation produced a calcium-dependent, slow depolarization in many cells which was not blocked by 100 microM hexamethonium or 1 microM atropine. A prolonged depolarization was also produced by local application of capsaicin (1 mM), which releases substance P and CGRP from afferent nerve terminals. Microinjection of the mammalian tachykinins substance P, neurokinin A and neurokinin B (all at 100 microM), also produced a slow depolarization. Application of specific agonists for the tachykinin receptor subtypes indicated that these neurons express both NK2 and NK3 receptors. Individual cells were filled with neurobiotin to examine their morphology and the preparations were counter-stained for SP-like immunoreactivity. The results demonstrated that SP-positive fibers are found in close apposition to both phasic and tonic neurons. From these results, we suggest that the parasympathetic neurons of the guinea-pig cardiac ganglion receive inputs from peptidergic, afferent fibers and that this input provides a pathway for potential local reflex control of cardiac function.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, University of Vermont, Burlington 05405, USA
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Abstract
1. The extent of recovery of endplate sensitivity following a 5 or 10 min exposure to carbachol was determined from measurements of miniature endplate current (m.e.p.c.) amplitudes in voltage-clamped snake twitch fibre endplates. M.e.p.c. amplitude recovery was dependent on the carbachol concentration (0.27-5.4 mM) and duration of application. Staurosporine pretreatment (0.5 microM for approximately 15 min) further decreased the extent of m.e.p.c. amplitude recovery. 2. The decrease in m.e.p.c. amplitude at control endplates exposed to high concentrations of agonist (5.4 mM carbachol for 10 min) was due to an apparent decrease in postsynaptic receptor density, not to a change in the conductance of the acetylcholine (ACh)-activated channels. 3. Pretreatment with either 1 microM lavendustin A or 50 microM KN-62 had no effect on m.e.p.c. amplitude recovery, whereas pretreatment with either 0.5 microM staurosporine, 50 microM sphingosine, or 0.5 microM calphostin C significantly reduced m.e.p.c. amplitude recovery following carbachol exposure. 4. Sphingosine and staurosporine produced a concentration-dependent decrease in the extent of m.e.p.c. amplitude recovery, but had no effect on m.e.p.c. characteristics in the absence of carbachol. In addition, this decrease in m.e.p.c. amplitude was not due to the presence of a subpopulation of small amplitude m.e.p.cs. 5. Prolonged treatment (18-20 h) of muscles with 200 nM phorbol 12-myristate 13-acetate (PMA), to down regulate protein kinase C, resulted in a significant reduction in m.e.p.c. amplitudes following exposure to carbachol. Conversely, treatment with 200 nM 4 alpha PMA, an inactive analogue, had no effect on m.e.p.c. amplitude recovery. 6. Only large amplitude ACh-activated channels (~50 pS) were recorded from fibres either in the presence of 50 micro M sphingosine or from fibres chronically exposed to PMA. However, following recovery from a 10 min exposure to 540 micro M carbachol, both small conductance (-25 pS) and large conductance ACh-activated channels were recorded in both sphingosine- and phorbol-treated preparations. The conductance of these two populations of channels was virtually identical to those seen in staurosporine treated fibres following carbachol exposure.7. We conclude that protein kinase C is required for full recovery of AChR sensitivity following carbachol-induced receptor inactivation. Exposure to high concentrations of agonist for prolonged periods appears to result in the inactivation of a subpopulation of receptors. These receptors must be replaced or reactivated by a process involving protein kinase C. When this phosphorylation step is inhibited, the AChRs remain in an activatable form, but with a reduced conductance.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405
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Abstract
1. The effect of colchicine treatment on acetylcholine receptor function was examined in potassium depolarized, voltage-clamped snake twitch fibre endplates. Receptor function was assessed by analysis of miniature endplate currents (m.e.p.c.) as well as acetylcholine (ACh)-induced single channel currents. 2. Pretreatment of snake muscle fibres with colchicine (10 microM to 100 microM) for 16-18 h had no effect on m.e.p.c. amplitude or decay rates. At higher concentrations (1 mM), there was a slight decrease in the average m.e.p.c. amplitude. 3. Colchicine produced a concentration-dependent decrease in the extent of m.e.p.c. amplitude recovery following a 10 min exposure to 540 microM carbachol. Exposure of 100 microM colchicine-treated preparations to 0.5 microM staurosporine further reduced the extent of m.e.p.c. amplitude recovery following carbachol exposure. 4. The decrease in m.e.p.c. amplitude following carbachol exposure was not due to a shift in the m.e.p.c. reversal potential. In addition, the distribution of m.e.p.c. amplitudes remained unimodal in both control and colchicine (100 microM)-treated preparations following carbachol exposure. 5. In addition to the normal, large conductance (approximately 48 pS) ACh-activated channels, a population of small conductance (approximately 29 pS) channels was observed in colchicine-treated preparations following exposure to carbachol. In preparations treated with both colchicine and staurosporine and then exposed to carbachol, the conductance of these small channels was identical to that of colchicine or staurosporine alone. 6. We suggest that prolonged exposure of snake twitch fibre endplates to agonist results in the activation and desensitization of ACh receptors. Furthermore, we propose that for a subpopulation of the inactivated receptors, restoration of function requires both the integrity of a subsynaptic cytoskeletal component and phosphorylation by a staurosporine-sensitive protein kinase. One plausible mechanism is that some receptors become destabilized in the membrane and phosphorylation of a cytoskeletal component, whose distribution may depend on an intact microtubular system, is required to re-anchor these receptors. If this anchoring process is inhibited either by disruption of the cytoskeleton with colchicine, or inhibition of the kinase by staurosporine, these receptors remain activatable, but have a reduced conductance.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405
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Hardwick JC, Parsons RL. Necessity of divalent cations for recovery from carbachol-induced nicotinic acetylcholine receptor inactivation at snake twitch fibre endplates. Br J Pharmacol 1993; 110:889-95. [PMID: 7694760 PMCID: PMC2175957 DOI: 10.1111/j.1476-5381.1993.tb13896.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. Previous studies demonstrated that elevation of the extracellular calcium concentration during a prolonged exposure to a high concentration of carbachol reverses the staurosporine-induced decrease in the extent of endplate resensitization in voltage-clamped snake twitch fibres. The present studies were designed to establish the site, specificity and potential mechanisms by which calcium could reverse the effects of staurosporine on acetylcholine receptor recovery. 2. Pretreatment of potassium-depolarized muscle preparations with 0.5 microM staurosporine, followed by a 10 min incubation with 540 microM carbachol, produced a significant decrease in the recovery of miniature endplate current (m.e.p.c.) amplitudes. Raising the extracellular calcium concentration from 1 mM to 10 mM during the agonist application reversed this inhibition. In addition, a brief (3 min) incubation in an elevated calcium (10 mM) solution in staurosporine-treated preparations previously exposed to 540 microM carbachol also reversed the reduction in m.e.p.c. amplitude. 3. Substitution of calcium with 10 mM strontium had no effect on the staurosporine-induced decrease in m.e.p.c. amplitude, whereas 10 mM magnesium partially substituted for calcium. Inclusion of (+)-tubocurarine (13 microM) in the 10 mM calcium solution to prevent the influx of calcium through agonist-activated channels did not prevent the reversal of the staurosporine-induced decrease in m.e.p.c. amplitudes. This suggested that the site of action of calcium on endplate resensitization was extracellular. 4. Analysis of acetylcholine (ACh)-induced single channel currents demonstrated that a population of small conductance channels seen only in the staurosporine-treated preparations following carbachol exposure, was still present in staurosporine-treated preparations incubated in 540 microM carbachol solution containing 10 mM calcium. Thus the effect of calcium on ACh receptor recovery was not due to the conversion of the small conductance channels to the normal, large conductance channels.5. Removal of calcium from the extracellular solution with the magnesium concentration unchanged,resulted in no change in the extent of m.e.p.c. amplitude recovery, nor did it alter the ability of staurosporine to inhibit recovery. Removal of both calcium and magnesium resulted in a significant decrease in the extent of recovery and staurosporine produced no additional decrease. This decrease in m.e.p.c. recovery in the divalent cation-free solution was not associated with a change in mean channel conductance as determined by noise analysis.6. Based on the results from these experiments, we suggest that, with prolonged exposure to agonist,some ACh receptors at the endplate become irreversibly inactivated. For full recovery of endplate sensitivity to occur, inactivated ACh receptors must be replaced. Part of the replacement ACh receptors appear to be recruited from a readily available but not previously activated pool and this process is dependent on extracellular calcium and/or magnesium. Thus, elevation of extracellular calcium may be able to reverse the apparent decrease in endplate sensitivity in staurosporine-treated fibres following carbachol exposure by increasing the number of functional receptors at the endplate.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405
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Coniglio LM, Hardwick JC, Parsons RL. Quantal transmitter release at snake twitch and tonic muscle fibres during prolonged nerve terminal depolarization. J Physiol 1993; 466:383-403. [PMID: 8410698 PMCID: PMC1175484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
1. Miniature endplate currents (MEPCs) were recorded in vitro from voltage-clamped twitch and tonic muscle fibres in costocutaneous muscles of the garter snake, Thamnophis. Recordings were made from fibres in a control sodium-containing solution and then during exposure to an isotonic potassium solution containing either 1.0 mM calcium and 4.2 mM magnesium or 3.6 mM calcium. The experiments were done at two levels of external calcium in order to demonstrate that the change in MEPC frequency was calcium dependent. During the initial exposure to the isotonic potassium solutions, the MEPC frequency was increased manyfold at both twitch and tonic fibres, but it declined progressively with continued exposure. MEPCs were recorded from both fibre types throughout a 20 h exposure to the isotonic potassium solution with 1 mM calcium, but no MEPCs were recorded at most twitch endplates after approximately 6 h in the isotonic potassium solution containing 3.6 mM calcium. In contrast, MEPCs were still present at tonic fibre endplates after 20 h in the isotonic potassium solution containing 3.6 mM calcium. 2. After 30 min in the isotonic potassium solution with 1 mM calcium, the MEPC amplitude recorded from both fibre types was approximately twice that in the control sodium-containing solution. At tonic endplates, the MEPC amplitude was also twofold greater in the isotonic potassium solution with 3.6 mM calcium than in sodium-containing solution. In contrast, after 30 min in the isotonic potassium solution containing 3.6 mM calcium, the MEPC amplitude at twitch endplates was similar to that in control solution. 3. In both fibre types, MEPC amplitude decreased progressively with continued exposure to the isotonic potassium solutions. The progressive decrease in MEPC amplitude was not due to a gradual decrease in postsynaptic sensitivity to acetylcholine. 4. The effects of high potassium were reversible as MEPCs were recorded at twitch fibre endplates in preparations which were returned to the control sodium-containing solution after a 20 h exposure to the isotonic potassium solution containing 3.6 mM calcium. 5. Ultrastructural examination showed that after a 6 h exposure to the isotonic potassium solutions most nerve terminals innervating twitch fibre endplates were devoid of synaptic vesicles whereas at the same time many synaptic vesicles were present in nerve terminals innervating tonic fibre endplates. Surprisingly, numerous synaptic vesicles were present in nerve terminals innervating either fibre type in muscle preparations exposed to the isotonic potassium solutions for 20 h.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- L M Coniglio
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405
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Abstract
1. Previously, we showed in voltage-clamped snake twitch muscle fibres that the extent of recovery of the nicotinic acetylcholine (ACh) receptor from carbachol-induced desensitization is reduced by pretreatment with the protein kinase inhibitor staurosporine. The present studies were undertaken to determine the mechanism underlying the staurosporine-induced inhibition of recovery. 2. Pretreatment with 0.5 microM staurosporine significantly decreased the extent of recovery of spontaneous miniature endplate current (m.e.p.c.) amplitudes in preparations exposed to 540 microM carbachol. The decrease in recovery of m.e.p.c. amplitude by staurosporine was dependent on the duration of carbachol exposure. No significant decrease in m.e.p.c. amplitude was observed with a 1 min exposure to agonist, whereas a significant decrease in recovery was seen with agonist exposures between 5-10 min. Further, the effect of staurosporine pretreatment on ACh receptor recovery was long-lasting such that m.e.p.c. amplitude remained decreased for at least 60 min. 3. Estimation of mean channel conductance by noise analysis during local perfusion of 20 microM carbachol demonstrated a decrease in conductance from 52 pS to 23 pS in staurosporine-treated preparations following recovery from desensitization. Staurosporine treatment in the absence of desensitization did not alter the mean channel conductance. 4. A single population of ACh-activated single channel currents with a conductance of 45-49 pS was recorded in cell-attached patches from enzymatically cleaned endplates in control and staurosporine-treated preparations not exposed to carbachol. 5. At staurosporine-treated endplates exposed to carbachol and then allowed to recover, a population of small conductance (23 pS) channels was observed. These channels were not normally seen in control preparations which had undergone carbachol-induced desensitization and recovery.6. We suggest that the decrease in m.e.p.c. amplitude observed following recovery from desensitization in staurosporine-treated endplates results from the activation of a mixture of small and large conductance ACh receptor channels.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, University of Vermont, Burlington 05405
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Abstract
A galanin-like peptide has been found in the parasympathetic fibers innervating the mudpuppy myocardium and direct application of galanin produces hyperpolarization of atrial myocytes and a decrease in twitch tension. In the present study, atrial and ventricular strips were incubated with galanin and then evaluated for changes in either phosphatidylinositol turnover or cyclic nucleotide levels. Galanin caused a significant and concentration-dependent increase in phosphatidylinositol turnover in both atrial and ventricular tissue. However, galanin had no effect on cyclic AMP or cyclic GMP levels in either basal or adrenergically-stimulated preparations. These results suggest that the galanin-induced cardio-inhibition in the mudpuppy may be mediated, at least in part, by a change in phosphatidylinositol turnover.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy and Neurobiology, College of Medicine, University of Vermont, Burlington 05405
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Konopka LM, Merriam LA, Hardwick JC, Parsons RL. Aminergic and peptidergic elements and actions in a cardiac parasympathetic ganglion. Can J Physiol Pharmacol 1992; 70 Suppl:S32-43. [PMID: 1284231 DOI: 10.1139/y92-241] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Correlated histochemical, immunocytochemical, and electrophysiological experiments have been undertaken to identify putative neurotransmitter-neuromodulator substances in cells and fibers in the parasympathetic cardiac ganglion of the mudpuppy, Necturus maculosus, and to determine the action of these agents on the properties of the parasympathetic postganglionic neurons. The mudpuppy cardiac ganglion contains two neuron types: large parasympathetic postganglionic neurons and smaller intrinsic neurons initially identified as small intensely fluorescent cells. We have shown that the postganglionic neurons contain both acetylcholine and a galanin-like neuropeptide. Also, we have demonstrated that the intrinsic neurons contain a number of different biogenic amines such as dopamine and serotonin, as well as neuropeptides including a substance P-like peptide and a galanin-like peptide. The results of these studies indicate that the anatomical and histochemical organization of the mudpuppy cardiac ganglion is more complex than that seen in other amphibians and is very similar to that found in most mammalian species. Previously, we showed that galanin has actions that make it of interest as a potential inhibitory neurotransmitter in the mudpuppy cardiac ganglion. Galanin hyperpolarizes and decreases membrane excitability in most parasympathetic neurons. Here we show that galanin initiates membrane hyperpolarization by activating a voltage- and time-dependent potassium conductance. We also present the initial results of ongoing studies which indicate that calcitonin gene-related peptide can depolarize some of the parasympathetic neurons as well as evidence that serotonin initiates depolarization in many parasympathetic neurons. This serotonin-induced depolarization consists of an initial transient depolarization followed by a longer, more slowly developing depolarization. Action potential activity is stimulated during the initial period of depolarization, but depressed during the later, slow depolarization. The results of these electrophysiological experiments suggest that many of the bioactive substances that have been identified in the different cells and nerve fibers within the cardiac ganglion affect the excitability of the postganglionic neurons. In conclusion, we suggest that the results of the studies summarized in this review demonstrate that the cardiac ganglion in the mudpuppy is not simply a relay station. Rather, the cardiac ganglion has a complex organization and exhibits a diversity of physiological responses, indicating that it very likely is another site of integration for control of cardiac function.
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Affiliation(s)
- L M Konopka
- Department of Anatomy and Neurobiology, University of Vermont College of Medicine, Burlington 05405
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Hardwick JC, Coniglio LM, Parsons RL. Staurosporine inhibits the extent of acetylcholine receptor recovery from carbachol-induced desensitization in snake twitch fibres. Br J Pharmacol 1991; 104:879-86. [PMID: 1810601 PMCID: PMC1908828 DOI: 10.1111/j.1476-5381.1991.tb12521.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
1. The effect of the protein kinase inhibitor, staurosporine, on the extent and time course of recovery following carbachol-induced desensitization was studied in snake twitch-muscle fibres maintained in an isotonic potassium propionate solution and voltage-clamped to +30 mV. 2. Pretreatment with staurosporine (0.5 microM) decreased the extent of recovery of spontaneous miniature endplate current (m.e.p.c.) amplitudes following desensitization by a sustained application of 540 microM carbachol. Recovery was inhibited by approximately 50% without altering the time course of m.e.p.c. recovery. 3. Staurosporine also produced a concentration-dependent (10 nM to 0.5 microM) decrease in the amplitude of a second carbachol-induced current, following a wash period, as compared to the amplitude of the current produced by the initial carbachol application. Pretreatment with 0.5 microM K252a, another wide spectrum protein kinase inhibitor, also decreased the extent of recovery of the response to a second carbachol application following desensitization. 4. Staurosporine pretreatment (0.5 microM) had no effect on either the kinetics of receptor-channel gating or the initial endplate sensitivity to agonist. This was determined by comparing the amplitude of the carbachol (540 microM)-induced currents and the amplitude and decay rate of m.e.p.cs in control and staurosporine-treated fibres. 5. Staurosporine had no effect on the time course of desensitization onset produced during the initial application of 540 microM carbachol or the depth of desensitization produced by the end of a 2-3 min exposure to 540 microM carbachol.6. Elevation of the external calcium concentration from 1 to 10mM during the 540 microM carbachol application completely antagonized the decreased extent of recovery of m.e.p.c. amplitude produced by pretreatment with 0.5 microM staurosporine.7. We suggest that phosphorylation of a population of acetylcholine receptors is required for complete recovery from desensitization, and that staurosporine inhibits the protein kinases responsible for this phosphorylation.8. We further propose that a transient increase in intracellular calcium, produced by an increase in calcium influx through agonist-activated endplate channels, stimulates additional protein kinase activity, which in turn, antagonizes the effect of staurosporine-treatment on recovery.
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Affiliation(s)
- J C Hardwick
- Department of Anatomy & Neurobiology, University of Vermont College of Medicine, Burlington 05405
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Abstract
This study examined the effects of extracellular ATP on norepinephrine (NE) uptake, using PC12 cells as a model of noradrenergic neurons. Previous experiments with synaptosomes led to the hypothesis that extracellular ATP can regulate NE uptake via an ecto-protein kinase. In the present study, we examined the high-affinity uptake of NE (referred to as uptake 1) in PC12 cells in the presence of varying concentrations of extracellular ATP. In the presence of Ca2+, low concentrations of ATP (0.1 microM) increased uptake 1 by approximately 36%. This increase could be mimicked by adenosine-5'-O-(3-thiotriphosphate) tetralithium salt (ATP gamma S), an analogue of ATP which can be utilized by protein kinases, and not by 5'-adenylylimidodiphosphate tetralithium salt, a nonhydrolyzable analogue of ATP, GTP, ADP, and adenosine also had no effect on uptake 1. Preincubation of the cells with NE and ATP gamma S, followed by washing and assaying NE uptake 30 min later, resulted in a persistent increase in uptake 1. Similar pretreatment with ATP did not show this increase; however, simultaneous pretreatment with ATP and ATP gamma S blocked the activation produced by ATP gamma S alone. Kinetic analysis showed that ATP gamma S pretreatment produces an increase in the Vmax of uptake 1 without altering the apparent Km for NE. These results support the hypothesis that extracellular ATP can regulate NE uptake via an ecto-protein kinase.
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Affiliation(s)
- J C Hardwick
- Department of Physiology and Biophysics, University of Vermont College of Medicine, Burlington 05405
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