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Halloran J, Lalande A, Zang M, Chodavarapu H, Riera CE. Monoclonal therapy against calcitonin gene-related peptide lowers hyperglycemia and adiposity in type 2 diabetes mouse models. Metabol Open 2020; 8:100060. [PMID: 33089134 PMCID: PMC7566843 DOI: 10.1016/j.metop.2020.100060] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 09/25/2020] [Indexed: 01/08/2023] Open
Abstract
Objective Calcitonin Gene-Related Peptide α (CGRPα) is a multifunctional neuropeptide found in the central and peripheral nervous system with cardiovascular, nociceptive, and gastrointestinal activities. CGRPα has been linked to obesity and insulin secretion but the role of this circulating peptide in energy metabolism remains unclear. Here, we thought to utilize a monoclonal antibody against circulating CGRPα to assess its ability to improve glucose homeostasis in mouse models of hyperglycemia and diabetes. Methods We examined the outcome of anti-CGRPα treatment in mouse models of diabetes and diet-induced obesity, using db/db mice, Streptozotocin (STZ) treatment to eliminate pancreatic islets, and high fat diet-fed mice. We also correlated these data with application of recombinant CGRPα peptide on cultured mature adipocytes to measure its impact on mitochondrial bioenergetics and fatty acid oxidation. Furthermore, we applied recombinant CGRPα to primary islets to measure glucose-stimulated insulin secretion (GSIS) and gene expression. Results BL6-db diabetic mice receiving anti-CGRPα treatment manifested weight loss, reduced adiposity, improved glucose tolerance, insulin sensitivity, GSIS and reduced pathology in adipose tissue and liver. Anti-CGRPα failed to modulate weight or glucose homeostasis in STZ-treated animals. High fat diet-fed mice showed reduced adiposity but no benefit on glucose homeostasis. Considering these findings, we postulated that CGRPα may have dual effects on adipocytes to promote lipid utilization while acting on pancreatic β-cells to modulate insulin secretion. Analysis of CGRPα in the pancreas showed that the peptide localized to insulin-positive cells and perivascular nerves surrounding islets. Ex-vivo analysis of pancreatic islets determined that CGRPα blocked GSIS and reduced insulin-2 gene expression. Mechanistical analysis revealed that recombinant CGRPα was able to reduce glycolytic capacity as well as fatty acid oxidation in primary white adipocytes. Conclusions These results establish a multifaceted role in energy metabolism for circulating CGRPα, with the ability to modulate thermogenic pathways in adipose tissue, as well as pancreatic β-cell dependent insulin secretion. Reducing circulating CGRPα levels with monoclonal therapy presents therapeutic potential for type 2 diabetes as shown in BL6-db/db mice but has reduced potential for models of hyperglycemia resulting from loss of β-cells (STZ treatment).
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Affiliation(s)
- Jonathan Halloran
- Center for Neural Science and Medicine, Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Department of Neurology, Cedars-Sinai Medical Center, 127 South San Vicente Boulevard, Los Angeles, CA, 90048, USA.,University of California, Berkeley, USA
| | - Alexandre Lalande
- Center for Neural Science and Medicine, Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Department of Neurology, Cedars-Sinai Medical Center, 127 South San Vicente Boulevard, Los Angeles, CA, 90048, USA
| | | | - Harshita Chodavarapu
- Center for Neural Science and Medicine, Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Department of Neurology, Cedars-Sinai Medical Center, 127 South San Vicente Boulevard, Los Angeles, CA, 90048, USA
| | - Céline E Riera
- Center for Neural Science and Medicine, Department of Biomedical Sciences, Board of Governors Regenerative Medicine Institute, Department of Neurology, Cedars-Sinai Medical Center, 127 South San Vicente Boulevard, Los Angeles, CA, 90048, USA.,David Geffen School of Medicine, University of California, Los Angeles, USA
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Janiuk I, Młynek K. Immunodetection of cocaine- and amphetamine-regulated transcript in bovine pancreas. Acta Histochem 2015; 117:545-50. [PMID: 25953739 DOI: 10.1016/j.acthis.2015.04.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Revised: 04/14/2015] [Accepted: 04/15/2015] [Indexed: 01/02/2023]
Abstract
This study was aimed at identifying and determining the configuration of structures which contain the cocaine- and amphetamine-regulated transcript peptide (CART) in the bovine pancreas. The study material was collected from 20 animals. The distribution of CART in the bovine pancreas was investigated, by an immunohistochemical evaluation. CART peptide in the normal pancreas has been identified in intrapancreatic ganglia, nerve fibres and in endocrine cells of Langerhans islets and exocrine pancreas. CART immunoreactive nerve fibres innervate the exocrine and endocrine regions and the intrapancreatic ganglia, where they form a moderate number of networks, encircling the cell bodies. The few CART-immunoreactive endocrine cells, that appear in the bovine pancreas, are not limited to the islet cells, where they form a subpopulation of CART-containing cells, but are also individually distributed in the exocrine region. Furthermore, CART has been visualized in nerve fibres, innervating pancreatic outlet ducts and blood vessels. CART plays a physiological role in the integrated mechanisms that regulate both endocrine and exocrine pancreatic secretion. These results are consistent with the hypothesis that CART expression in nerve fibres and intrapancreatic ganglia is a common feature of the mammalian pancreas, whereas its expression in endocrine cells appears to be restricted to single cells of the bovine pancreas.
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Bayrakdar A, Yaman M, Atalar O, Gencer Tarakci B, Ceribasi S. Distribution of neuropeptides in endocrine and exocrine pancreas of long-legged buzzard (Buteo rufinus): An immunohistochemical study. ACTA ACUST UNITED AC 2011; 166:121-7. [DOI: 10.1016/j.regpep.2010.10.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2010] [Revised: 10/02/2010] [Accepted: 10/13/2010] [Indexed: 11/28/2022]
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Amella C, Cappello F, Kahl P, Fritsch H, Lozanoff S, Sergi C. Spatial and temporal dynamics of innervation during the development of fetal human pancreas. Neuroscience 2008; 154:1477-87. [DOI: 10.1016/j.neuroscience.2008.04.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 04/21/2008] [Accepted: 04/22/2008] [Indexed: 01/13/2023]
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di Mola FF, di Sebastiano P. Pain and pain generation in pancreatic cancer. Langenbecks Arch Surg 2008; 393:919-22. [PMID: 18193269 DOI: 10.1007/s00423-007-0277-z] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Accepted: 11/16/2007] [Indexed: 12/23/2022]
Abstract
BACKGROUND Pain can be a frequent symptom during the natural history of a patient with pancreatic cancer. An increase in incidence with disease progression and the presence of unbearable pain may preclude a curative resection. MATERIALS AND METHODS Even in those patients with resectable pancreatic cancer, the presence of pain has an impact on prognosis. To date, we do not really know why some patients develop pain. RESULTS Perineural cancer cell invasion is one of the most intriguing characteristics of this neoplasia and may in some cases explain the pain sensation. In addition, so-called "neurogenic inflammation" might also play a role in pain generation in pancreatic cancer, just like in chronic pancreatitis. CONCLUSION In conclusion, understanding the mechanisms of pain in pancreatic cancer could help patients because what counts is not only 5-year survival but also median survival with good quality of life.
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Affiliation(s)
- Fabio F di Mola
- Department of Abdominal Surgery, IRCCS-Casa Sollievo della Sofferenza, San Giovanni Rotondo, Foggia, Italy
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Gram DX, Ahrén B, Nagy I, Olsen UB, Brand CL, Sundler F, Tabanera R, Svendsen O, Carr RD, Santha P, Wierup N, Hansen AJ. Capsaicin-sensitive sensory fibers in the islets of Langerhans contribute to defective insulin secretion in Zucker diabetic rat, an animal model for some aspects of human type 2 diabetes. Eur J Neurosci 2007; 25:213-23. [PMID: 17241282 DOI: 10.1111/j.1460-9568.2006.05261.x] [Citation(s) in RCA: 107] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The system that regulates insulin secretion from beta-cells in the islet of Langerhans has a capsaicin-sensitive inhibitory component. As calcitonin gene-related peptide (CGRP)-expressing primary sensory fibers innervate the islets, and a major proportion of the CGRP-containing primary sensory neurons is sensitive to capsaicin, the islet-innervating sensory fibers may represent the capsaicin-sensitive inhibitory component. Here, we examined the expression of the capsaicin receptor, vanilloid type 1 transient receptor potential receptor (TRPV1) in CGRP-expressing fibers in the pancreatic islets, and the effect of selective elimination of capsaicin-sensitive primary afferents on the decline of glucose homeostasis and insulin secretion in Zucker diabetic fatty (ZDF) rats, which are used to study various aspects of human type 2 diabetes mellitus. We found that CGRP-expressing fibers in the pancreatic islets also express TRPV1. Furthermore, we also found that systemic capsaicin application before the development of hyperglycemia prevents the increase of fasting, non-fasting, and mean 24-h plasma glucose levels, and the deterioration of glucose tolerance assessed on the fifth week following the injection. These effects were accompanied by enhanced insulin secretion and a virtually complete loss of CGRP- and TRPV1-coexpressing islet-innervating fibers. These data indicate that CGRP-containing fibers in the islets are capsaicin sensitive, and that elimination of these fibers contributes to the prevention of the deterioration of glucose homeostasis through increased insulin secretion in ZDF rats. Based on these data we propose that the activity of islet-innervating capsaicin-sensitive fibers may have a role in the development of reduced insulin secretion in human type 2 diabetes mellitus.
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Affiliation(s)
- Dorte X Gram
- Research and Development, Novo Nordisk A/S, Novo Nordisk Park, F6.1.30, DK-2760 Måløv, Denmark.
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Abstract
The expression of DbetaH and several neuropeptides was investigated in neuronal elements of the ovine pancreas using double immunocytochemical stainings. Immunoreactivities to DbetaH, NPY, VIP and SP were seen to various extents in nerve terminals associated with the acini, islets, ducts, blood vessels, interlobular connective tissue as well as in the neurons of intrapancreatic ganglia. The expression of CGRP was limited to nerve fibers lying in the connective tissue septa, amongst the acini and in close vicinity to the pancreatic blood vessels. Single GRP-positive nerve endings were located around the acini, ducts and in the interlobular connective tissue. With the exception of the ductal system in a co-localization of NPY with DbetaH was frequently found in all regions of the pancreas. Moderately numerous blood vessel-associated VIP-positive nerve fibers as well as the vast majority of VIP-containing intrapancreatic neurons were found to co-express DbetaH. Single SP-immunoreactive (IR) nerve fibers of the exocrine pancreas and interlobular connective tissue as well as SP-positive intrapancreatic neurons additionally showed the presence of DbetaH. The co-localization of VIP and NPY was found in nerve terminals located around the blood vessels and acini, in the connective tissue septa as well as in numerous pancreatic neuronal perikarya. Rare nerve terminals located between the acini and around small blood vessels as well as several neurons of intrapancreatic ganglia were VIP-IR/ SP-IR. Simultaneous expression of SP and CGRP was found in nerve fibers supplying large pancreatic arteries and veins, interlobular connective tissue and, occasionally, around the acini. Throughout the pancreas the population of CGRP-positive nerve endings showed lack of VIP and NPY. In a moderate number of GRP-containing nerve fibers, a co-expression of NPY was noted. Nerve terminals containing both GRP and VIP were detected sporadically, whereas none of the GRP-positive nerve terminals showed expression of SP. We conclude that the presented noradrenergic as well as peptidergic innervation patterns of the ovine pancreas are species-dependent. On the basis of the occurrence of DbetaH, NPY, VIP and SP (alone or in combination) in pancreatic neuronal elements we can suggest that these substances presumably act as regulators of the endocrine and/or exocrine pancreas. Involvement of CGRP and GRP in the ovine pancreas physiology seems to be of minor importance. The co-localization study indicated that the pancreas of the sheep is innervated from several sources including intrinsic as well as extrinsic ganglia.
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Affiliation(s)
- Marcin Bartłomiej Arciszewski
- Department of Animal Anatomy and Histology, Faculty of Veterinary Medicine, Agricultural University, Akademicka 12, 20-033 Lublin, Poland.
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Sevcik MA, Jonas BM, Lindsay TH, Halvorson KG, Ghilardi JR, Kuskowski MA, Mukherjee P, Maggio JE, Mantyh PW. Endogenous opioids inhibit early-stage pancreatic pain in a mouse model of pancreatic cancer. Gastroenterology 2006; 131:900-10. [PMID: 16952558 PMCID: PMC2100397 DOI: 10.1053/j.gastro.2006.06.021] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2005] [Accepted: 06/08/2006] [Indexed: 01/26/2023]
Abstract
BACKGROUND & AIMS The endogenous opioid system is involved in modulating the experience of pain, the response to stress, and the action of analgesic therapies. Recent human imaging studies have shown a significant tonic modulation of visceral pain, raising the question of whether endogenous opioids tonically modulate the pain of visceral cancer. METHODS Transgenic mice expressing the first 127 amino acids of simian virus 40 large T antigen, under the control of the rat elastase-1 promoter, that spontaneously develop pancreatic cancer were used to investigate the role of endogenous opioids in the modulation of pancreatic cancer pain. Visceral pain behaviors were assessed as degree of hunching and vocalization. RESULTS Although mice with late-stage pancreatic cancer displayed spontaneous, morphine-reversible, visceral pain-related behaviors such as hunching and vocalization, these behaviors were absent in mice with early-stage pancreatic cancer. After systemic administration of the central nervous system (CNS)-penetrant opioid receptor antagonists naloxone or naltrexone, mice with early-stage pancreatic cancer displayed significant visceral pain-related behaviors, whereas systemic administration of the CNS-nonpenetrant opioid antagonist naloxone-methiodide did not induce an increase in visceral pain behaviors. CONCLUSIONS Our findings suggest that a CNS opioid-dependent mechanism tonically modulates early and late-stage pancreatic cancer pain. Understanding the mechanisms that mask this pain in early stage disease and drive this pain in late-stage disease may allow improved diagnosis, treatment, and care of patients with pancreatic cancer.
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Affiliation(s)
- Molly A. Sevcik
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Beth M. Jonas
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Theodore H. Lindsay
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Kyle G. Halvorson
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
| | - Joseph R. Ghilardi
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Research Service, Veterans Affairs Medical Center, Minneapolis, MN 55417
| | - Michael A. Kuskowski
- Geriatric Research Education and Clinical Center (GRECC), Veterans Affairs Medical Center, Minneapolis, MN 55417
| | - Pinku Mukherjee
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Scottsdale, AZ 85259
| | - John E. Maggio
- Department of Pharmacology and Cell Biophysics, University of Cincinnati, Cincinnati, OH 45267
| | - Patrick W. Mantyh
- Neurosystems Center and Departments of Diagnostic and Biological Sciences, Psychiatry, Neuroscience, and Cancer Center, University of Minnesota, Minneapolis, MN 55455
- Research Service, Veterans Affairs Medical Center, Minneapolis, MN 55417
- Correspondence to Patrick W. Mantyh: Neurosystems Center, 18-208 Moos Tower, University of Minnesota, 515 Delaware Street SE, Minneapolis, MN 55455, Phone: (612) 626-0180, Fax: (612) 626-2565,
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Lindsay TH, Halvorson KG, Peters CM, Ghilardi JR, Kuskowski MA, Wong GY, Mantyh PW. A quantitative analysis of the sensory and sympathetic innervation of the mouse pancreas. Neuroscience 2006; 137:1417-26. [PMID: 16388907 DOI: 10.1016/j.neuroscience.2005.10.055] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Revised: 10/04/2005] [Accepted: 10/18/2005] [Indexed: 10/25/2022]
Abstract
Pain from pancreatitis or pancreatic cancer can be both chronic and severe although little is known about the mechanisms that generate and maintain this pain. To define the peripheral sensory and sympathetic fibers involved in transmitting and modulating pancreatic pain, immunohistochemistry and confocal microscopy were used to examine the sensory and sympathetic innervation of the head, body and tail of the normal mouse pancreas. Myelinated sensory fibers were labeled with an antibody raised against 200 kD neurofilament H (clone RT97), thinly myelinated and unmyelinated peptidergic sensory fibers were labeled with antibodies raised against calcitonin gene-related peptide (CGRP) and post-ganglionic sympathetic fibers were labeled with an antibody raised against tyrosine hydroxylase (TH). RT97, CGRP, and TH immunoreactive fibers were present in parenchyma of the head, body and tail of the pancreas with the relative density of both RT97 and CGRP expressing fibers being head>body>tail, whereas for TH, a relatively even distribution was observed. In all three regions of the pancreas, RT97 fibers were associated mainly with large blood vessels, the CGRP fibers were associated with the large- and medium-sized blood vessels and the TH were associated with the large- and medium-sized blood vessels as well as capillaries. In addition to this extensive set of sensory and sympathetic nerve fibers that terminate in the pancreas, there were large bundles of en passant nerve fibers in the dorsal region of the pancreas that expressed RT97 or CGRP and were associated with the superior mesenteric plexus. These data suggest the pancreas receives a significant sensory and sympathetic innervation. Understanding the factors and disease states that sensitize and/or directly excite the nerve fibers that terminate in the pancreas as well as those that are en passant may aid in the development of therapies that more effectively modulate the pain that frequently accompanies diseases of the pancreas, such as pancreatitis and pancreatic cancer.
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Affiliation(s)
- T H Lindsay
- Neurosystems Center and Department of Diagnostic and Biological Sciences, University of Minnesota, and Research Service, Veterans Affairs Medical Center, Minneapolis, MN 55455, USA
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Lindsay TH, Jonas BM, Sevcik MA, Kubota K, Halvorson KG, Ghilardi JR, Kuskowski MA, Stelow EB, Mukherjee P, Gendler SJ, Wong GY, Mantyh PW. Pancreatic cancer pain and its correlation with changes in tumor vasculature, macrophage infiltration, neuronal innervation, body weight and disease progression. Pain 2005; 119:233-246. [PMID: 16298491 DOI: 10.1016/j.pain.2005.10.019] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2005] [Revised: 08/08/2005] [Accepted: 10/17/2005] [Indexed: 12/21/2022]
Abstract
To begin to understand the relationship between disease progression and pain in pancreatic cancer, transgenic mice that develop pancreatic cancer due to the expression of the simian virus 40 large T antigen under control of the rat elastase-1 promoter were examined. In these mice precancerous cellular changes were evident at 6 weeks and these included an increase in: microvascular density, macrophages that express nerve growth factor and the density of sensory and sympathetic fibers that innervate the pancreas, with all of these changes increasing with tumor growth. In somatic tissue such as skin, the above changes would be accompanied by significant pain; however, in mice with pancreatic cancer, changes in pain-related behaviors, such as morphine-reversible severe hunching and vocalization only became evident at 16 weeks of age, by which time the pancreatic cancer was highly advanced. These data suggest that in mice as well as humans, there is a stereotypic set of pathological changes that occur as pancreatic cancer develops, and while weight loss generally tracks disease progression, there is a significant lag between disease progression and behaviors indicative of pancreatic cancer pain. Defining the mechanisms that mask this pain in early and mid-stage disease and drive the pain in late-stage disease may aid in earlier diagnosis, survival, and increased quality of life of patients with pancreatic cancer.
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Affiliation(s)
- Theodore H Lindsay
- Neurosystems Center, 18-208 Moos Tower, School of Dentistry, University of Minnesota, 515 Delaware Street SE, Minneapolis, MN 55455, USA Research Service, VA Medical Center, Minneapolis, MN 55417, USA GRECC, VA Medical Center, Minneapolis, MN 55417, USA Department of Pathology, University of Virginia, Charlottesville, VA 22908, USA Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Scottsdale, AZ 85259, USA Department of Anesthesiology, Division of Pain Medicine, Mayo Clinic College of Medicine, Rochester, MN 55905, USA
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Bertelli E, Bendayan M. Association between endocrine pancreas and ductal system. More than an epiphenomenon of endocrine differentiation and development? J Histochem Cytochem 2005; 53:1071-86. [PMID: 15956021 DOI: 10.1369/jhc.5r6640.2005] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Traditional histological descriptions of the pancreas distinguish between the exocrine and the endocrine pancreas, as if they were two functionally distinct glands. This view has been proven incorrect and can be considered obsolete. Interactions between acinar and islet tissues have been well established through numerous studies that reveal the existence of anatomical and functional relationships between these compartments of the gland. Less attention, however, has traditionally been paid to the relationships occurring between the endocrine pancreas and the ductal system. Associations between islet tissue and ducts are considered by most researchers as only a transient epiphenomenon of endocrine development. This article reviews the evidence that has emerged in the last 10 years demonstrating the existence of stable, close, and systematic relationships between these two pancreatic compartments. Functional and pathophysiological implications are considered, and the existence of an "acinar-duct-islet" axis is put forward. The pancreas appears at present to be an integrated organ composed of three functionally related components of well-orchestrated endocrine and exocrine physiological responses.
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Affiliation(s)
- Eugenio Bertelli
- Department of Pharmacology Giorgio Segre, Section of Morphology, University of Siena, Via Aldo Moro 4, I-53100 Siena, Italy.
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Glatzle J, Sternini C, Robin C, Zittel TT, Wong H, Reeve JR, Raybould HE. Expression of 5-HT3 receptors in the rat gastrointestinal tract. Gastroenterology 2002; 123:217-26. [PMID: 12105850 DOI: 10.1053/gast.2002.34245] [Citation(s) in RCA: 130] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND & AIMS Functional effects mediated via the 5-hydroxytryptamine3 receptor (5-HT3R) can be elicited from both extrinsic and intrinsic neurons innervating the gastrointestinal (GI) tract. Clinically, 5-HT3 antagonists are important in the treatment of emesis and have been used for the treatment of symptoms in functional bowel disease. The aim of the present study was to elucidate the cellular sites of 5-HT3R expression in the rat GI tract using immunohistochemistry. METHODS Immunohistochemistry was performed in fixed cryostat sections and whole mounts of stomach and intestine of fasted rats, using an affinity-purified antibody directed to a 19-amino acid sequence of the cytoplasmic loop of the 5-HT3R. RESULTS 5-HT3R immunoreactivity was localized to numerous neurons of the myenteric and submucosal plexus, concentrated primarily near the neuronal plasma membrane, and to fibers in the circular and longitudinal muscles, submucosa, and mucosa. 5-HT3R immunoreactivity was also expressed by interstitial cells of Cajal and a few endocrine cells. Numerous 5-HT3R-positive myenteric neurons were cholinergic, and few neurons coexpressed VIP or SP immunoreactivity. Fibers immunoreactive for 5-HT3R in the duodenal but not ileal mucosa were markedly reduced by subdiaphragmatic vagotomy or chemical denervation of vagal afferents. CONCLUSIONS These findings indicate that 5-HT3Rs are expressed by distinct cells in the GI tract, including functionally distinct classes of neurons, interstitial cells of Cajal, and endocrine cells. The effects of serotonin mediated by 5-HT3Rs involve the activation of neuronal and nonneuronal pathways.
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Affiliation(s)
- Jörg Glatzle
- Department of Anatomy, Physiology, and Cell Biology, University of California Davis School of Veterinary Medicine, Davis, California 95616, USA
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Cooper GJS. Amylin and Related Proteins: Physiology and Pathophysiology. Compr Physiol 2001. [DOI: 10.1002/cphy.cp070210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Kieffer TJ, Hussain MA, Habener JF. Glucagon and Glucagon‐like Peptide Production and Degradation. Compr Physiol 2001. [DOI: 10.1002/cphy.cp070208] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Jin C, Naruse S, Kitagawa M, Ishiguro H, Nakajima M, Mizuno N, Ko SB, Hayakawa T. The effect of calcitonin gene-related peptide on pancreatic blood flow and secretion in conscious dogs. REGULATORY PEPTIDES 2001; 99:9-15. [PMID: 11257309 DOI: 10.1016/s0167-0115(01)00214-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The effects of human alpha-calcitonin gene-related peptide (alpha-CGRP) and beta-CGRP on pancreatic arterial (PA), superior mesenteric (SMA) and left gastric arterial (LGA) blood flows were studied by ultrasound transit-time blood flow meters in five conscious dogs. Intravenous injections of alpha-CGRP and beta-CGRP (5-200 pmol/kg) induced a dose-related increase in PA flow and a dose-related decrease in its resistance. At lower doses, alpha-CGRP was more potent than beta-CGRP, but their maximal responses were similar. The blood flow responses to alpha-CGRP (200 pmol/kg) were 153% of the basal flow in LGA, 313% in PA, and 534% in SMA, while those to VIP (100 pmol/kg) were 467% in LGA, 953% in PA and 163% in SMA. Somatostatin reduced blood flow in all arteries. alpha-CGRP, but not beta-CGRP, at higher doses induced gastric contractions and pancreatic protein-rich secretion, which were blocked by atropine. These results suggest that CGRP in perivascular nerves in the pancreas may regulate pancreatic blood flow in dogs but its physiological function remains to be studied.
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Affiliation(s)
- C Jin
- Internal Medicine II, Nagoya University School of Medicine, 65 Tsurumai-cho, Nagoya 466-8550, Showa, Japan.
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Myojin T, Kitamura N, Hondo E, Baltazar ET, Pearson GT, Yamada J. Immunohistochemical localization of neuropeptides in bovine pancreas. Anat Histol Embryol 2000; 29:167-72. [PMID: 10916879 DOI: 10.1046/j.1439-0264.2000.00257.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The occurrence and density of distribution of nerves and endocrine cells that are immunoreactive for neuropeptides in the bovine pancreas were studied by immunohistochemistry. The six neuropeptides localized were galanin (GAL), substance P (SP), methionine-enkephalin (MENK), neuropeptide Y (NPY), calcitonin gene-related peptide (CGRP) and vasoactive intestinal polypeptide (VIP). The exocrine pancreas was shown to have an appreciable number of GAL- and SP-immunoreactive nerve fibres but few fibres showing immunoreactivity for VIP and CGRP. Numerous MENK-, GAL-, SP-, and NPY-immunoreactive nerve fibres were seen in the endocrine portion of the pancreas. Nerve cell bodies in the intrapancreatic ganglia showed immunoreactivity for all of the neuropeptides except CGRP. Endocrine cells showing immunoreactivity for GAL and SP were observed in the large islets and islets of Langerhans, respectively. The present results indicate a characteristic distribution of neuropeptides in the bovine pancreas, which may regulate both exocrine and endocrine secretions of pancreas.
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Affiliation(s)
- T Myojin
- Department of Veterinary Anatomy, Obihiro University of Agriculture and Veterinary Medicine, Japan
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Abstract
Functional alterations are developed in transplanted islets over time. Because islets in situ are densely innervated and isolation disconnects the endocrine organ from extrinsic nerves and from ganglia in the exocrine pancreas, it is important to examine the reinnervation of islet grafts. This review describes the patterns of appearances of intrinsic perikarya and reinnervating fibers demonstrating markers for parasympathetic, sympathetic or sensory nerve substances, most notably neuropeptides, in islet transplants. An altered innervation pattern, as compared to normal islets, develops. Presumably the expression of neuronal markers in the grafts is related to factors both in the islets and in the ectopic environment offered by the implantation organ.
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Affiliation(s)
- S Persson-Sjögren
- Department of Integrative Medical Biology, Section for Histology and Cell Biology, Umeâ University, SE-901 87, Umeâ, Sweden.
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De Girolamo P, Lucini C, Vega JA, Andreozzi G, Coppola L, Castaldo L. Co-localization of Trk neurotrophin receptors and regulatory peptides in the endocrine cells of the teleostean stomach. THE ANATOMICAL RECORD 1999; 256:219-26. [PMID: 10521780 DOI: 10.1002/(sici)1097-0185(19991101)256:3<219::aid-ar1>3.0.co;2-n] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Recently it has been observed that a subpopulation of gut endocrine cells in vertebrates express Trk-like proteins, suggesting that neurotrophins could regulate the synthesis and storage of amines and peptides of these cells. Nevertheless, the peptides and amines present in the endocrine cells that express Trks have not been characterized. In this study we used immunohistochemistry to investigate the occurrence of Trk-like proteins (TrkA-like, TrkB-like and TrkC-like) and the possible co-localization of these with peptides and/or biogenic amines in the endocrine cells of the stomach of three teleost (bass, gilt-head and scorpionfish). No TrkA-like immunoreactivity (IR) was detected in the stomach of these species, whereas TrkB-like IR and TrkC-like IR were observed in numerous cells of the gastric epithelium. TrkB-like immunoreactive cells were present in all three species examined, and were particularly abundant in the blind sac. Conversely, TrkC-like immunoreactive cells were found only in the bass stomach, apparently co-localized with TrkB-like IR. TrkB-like IR was found co-localized with somatostatin IR in scorpionfish, and with somatostatin and CGRP IR in gilt-head and bass. Gastric endocrine cells expressing 5-HT, glucagon, insulin, met-, leu-enkephalin, substance P, PYY, VIP, CCK, NPY, bombesin and motilin were unreactive for Trk-like proteins. The present results provide direct evidence for the occurrence of Trk-like neurotrophin receptor proteins in a subpopulation of the teleostean gastric endocrine cells and suggest that neurotrophins could regulate, as in neurons, the expression of some neuropeptides such as somatostatin and CGRP.
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Affiliation(s)
- P De Girolamo
- Dipartimento di Strutture, Funzioni, e Tecnologie Biologiche, Università di Napoli "Federico II," 80137 Naples, Italy.
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Persson-Sjögren S, Forsgren S, Täljedal IB. Expression of tyrosine hydroxylase, calcitonin gene-related peptide, substance P and protein gene product 9.5 in mouse islets transplanted under the kidney capsule. Neuropeptides 1998; 32:307-18. [PMID: 10102675 DOI: 10.1016/s0143-4179(98)90053-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pancreatic islets transplanted to the kidney of syngeneic mice were stained for calcitonin gene-related peptide (CGRP), substance P (SP), tyrosine hydroxylase (TH), acetylcholinesterase and the pan-neuronal marker, protein gene product 9.5 (PGP). Nerve fibers expressing TH-like immunoreactivity (TH-LI) and CGRP-LI were rare for 4 days but increased 2 (CGRP) or 6 (TH) weeks after transplantation. In 1-year-old grafts the CGRP-LI innervation resembled that in situ, while TH-LI and PGP-LI innervations were increased. SP-LI fibers remained rare throughout. Perikarya intrinsic to the islets did not show CGRP-LI or SP-LI. The results indicate a progressive ingrowth of sensory fibers into the grafts and that the TH-LI innervation becomes even more pronounced than in the pancreas. The post-transplantation reaction of islet intrinsic neurons does not involve CGRP and SP, contrasting with previous observations for vasoactive intestinal polypeptide.
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20
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Jaworek J, Konturek SJ, Szlachcic A. The role of CGRP and afferent nerves in the modulation of pancreatic enzyme secretion in the rat. INTERNATIONAL JOURNAL OF PANCREATOLOGY : OFFICIAL JOURNAL OF THE INTERNATIONAL ASSOCIATION OF PANCREATOLOGY 1997; 22:137-46. [PMID: 9387036 DOI: 10.1007/bf02787472] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
CONCLUSION Stimulation of pancreatic sensory nerves by capsaicin produced secretory effects probably caused, at least in part, by the release of CGRP. BACKGROUND In the pancreas calcitonin gene-related peptide (CGRP) has been localized in the sensory nerves, but its physiological role is unknown. This study was undertaken to compare the changes of pancreatic enzyme secretion produced by CGRP and by stimulation or destruction of sensory nerves. METHODS To stimulate sensory nerves, low doses of capsaicin (0.25-0.5 mg/kg) were given intraduodenally to the conscious rats with chronic pancreatic fistula. To inactivate sensory nerves high doses of capsaicin (100 mg/kg) were given subcutaneously 10 d before tests. For the in vitro experiments pancreatic slices and isolated pancreatic acini were prepared from intact and capsaicin-denervated rats. RESULTS In conscious rats, CGRP given subcutaneously (5-10 micrograms/kg) and low doses of capsaicin given intraduodenally reduced basal pancreatic secretion. In isolated pancreatic acini, CGRP (10(-10)-10(-6) M), but not capsaicin, increased basal or secretagog-stimulated amylase release. In pancreatic slices (containing nerve fibers) capsaicin (10(-10)-10(-6) M) increased enzyme secretion, and this secretion was abolished by previous inactivation of sensory nerves by this neurotoxin. Capsaicin deactivation did not affect the secretory response of pancreatic acini to CGRP, cerulein, or urecholine. Sensory denervation by capsaicin did not change basal protein secretion, but reduced that produced by feeding or diversion of pancreatic juice to the exterior during first 2 h of the tests.
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Affiliation(s)
- J Jaworek
- Institute of Physiology, Colleguim Medicum Jagiellonian University, Kraków, Poland
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21
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Brunicardi FC, Shavelle DM, Andersen DK. Neural regulation of the endocrine pancreas. INTERNATIONAL JOURNAL OF PANCREATOLOGY : OFFICIAL JOURNAL OF THE INTERNATIONAL ASSOCIATION OF PANCREATOLOGY 1995; 18:177-95. [PMID: 8708389 DOI: 10.1007/bf02784941] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- F C Brunicardi
- Department of Surgery, Baylor College of Medicine, Houston, TX 77030, USA
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22
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Myrsén U, Sundler F. Neuropeptide Y is expressed in islet somatostatin cells of the hamster pancreas: a combined immunocytochemical and in situ hybridization study. REGULATORY PEPTIDES 1995; 57:65-76. [PMID: 7644704 DOI: 10.1016/0167-0115(95)00020-c] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Neuropeptide Y (NPY) is known to occur in the autonomic nervous system, including the pancreatic islet innervation. We now present evidence that NPY is also expressed in endocrine islet cells in hamster pancreas. Thus, NPY-immunoreactivity and gene expression were detected in peripheral islet cells, using immunocytochemistry (ICC), in situ hybridization (ISH), and a combination of these techniques. Double immunostaining for NPY and somatostatin enabled localisation of NPY ot the vast majority of the somatostatin cells. However, a few somatostatin cells were devoid of NPY immunoreactivity and an occasional NPY-immunoreactive cell was devoid of somatostatin. ISH with an NPY mRNA specific probe, showed labelling of cells in the islet periphery. Furthermore, combined ISH for NPY mRNA and ICC for somatostatin showed autoradiographic labelling of somatostatin cells to a varying degree. Both somatostatin and NPY are inhibitors of insulin and/or glucagon secretion. Thus, in the islets these two peptides may be coreleased and cooperate in the regulation of islet hormone secretion. The role for NPY emanating from islet cells is probably paracrine rather than endocrine.
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Affiliation(s)
- U Myrsén
- Department of Medical Cell Research, University of Lund, Sweden
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23
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De Giorgio R, Zittel TT, Parodi JE, Becker JM, Brunicardi FC, Go VL, Brecha NC, Sternini C. Peptide immunoreactivities in the ganglionated plexuses and nerve fibers innervating the human gallbladder. JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM 1995; 51:37-47. [PMID: 7722214 DOI: 10.1016/0165-1838(95)80005-u] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The mammalian gallbladder is innervated by a well-developed intrinsic neural network. However, little is known about the neurochemistry and organization of the innervation of this organ in humans. The aim of this study was to analyze the distribution of immunoreactivity (IR) for the neuropeptides, vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), tachykinins (TK) and calcitonin gene-related peptide (CGRP) in the human gallbladder by means of immunohistochemistry. Neuropeptide-IRs are found in neurons and processes of the two ganglionated plexuses, i.e., the innermost plexus located in the lamina propria at the base of the mucosal folds, and the outermost plexus situated within the fibro-muscular layer. In these two plexuses, VIP-, NPY- and TK-IRs are present in ganglion cells and varicose fibers, whereas CGRP-IR is confined to nerve processes. VIP-IR is present in most, if not all, neurons. NPY- and TK-IRs are also found in many neurons. The densities of the peptide-IR nerves in the mucosa are NPY and VIP > TK >> CGRP, and in the fibro-muscular layer are NPY > VIP and TK > CGRP. The vasculature is richly innervated by NPY-IR nerves, which are mostly perivascular. CGRP-, VIP- and TK-IR processes are found only occasionally around blood vessels and in a paravascular position. Double-label studies demonstrated that a large number of VIP-containing neurons expresses NPY- or TK-IR. On the other hand, all neurons positive for either NPY- or TK-IR are immunostained for VIP. In agreement with these findings, most of the NPY-IR fibers in the lamina propria and fibro-muscular layer contain VIP-IR, and numerous TK-IR fibers are positive for VIP. However, the perivascular NPY-IR processes do not contain VIP-IR, suggesting an extrinsic origin. In addition, a population of TK-IR processes contains CGRP-IR and presumably originates from extrinsic sources, since CGRP/TK-IR intrinsic neurons could not be detected in the gallbladder. Peptide-IRs have a similar distribution in the neck, body and fundus of the gallbladder. No peptide-containing endocrine/paracrine cells are observed in the epithelium. The presence of peptide-IRs in the ganglionated plexuses and the abundance of peptidergic innervation suggest that peptides exert their effects on gallbladder function by acting directly on tissue targets and influencing intrinsic ganglion cells. Furthermore, the co-localization of more than one peptide in the same neuron raises the possibility that peptides are co-released upon stimulation and might interact at the same target.
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Affiliation(s)
- R De Giorgio
- CURE: VA/UCLA Gastroenteric Biology Center VAMC-Wadsworth 90073, USA
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24
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Maggi CA. Tachykinins and calcitonin gene-related peptide (CGRP) as co-transmitters released from peripheral endings of sensory nerves. Prog Neurobiol 1995; 45:1-98. [PMID: 7716258 DOI: 10.1016/0301-0082(94)e0017-b] [Citation(s) in RCA: 345] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
- C A Maggi
- Department of Pharmacology, A. Menarini Pharmaceuticals, Florence, Italy
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25
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Lakomy M, Kaleczyc J, Majewski M, Sienkiewicz W. Peptidergic innervation of the bovine vagina and uterus. Acta Histochem 1995; 97:53-66. [PMID: 7771184 DOI: 10.1016/s0065-1281(11)80206-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The distribution of neuropeptide Y, substance P, vasoactive intestinal polypeptide, Leu5-enkephalin, bombesin/gastrin-releasing peptide, calcitonin gene-related peptide, somatostatin, cholecystokinin and catecholamine synthesizing enzymes, tyrosine hydroxylase and dopamine-beta-hydroxylase was studied immunohistochemically in nerve fibres supplying the bovine vagina and uterus. The nerves containing tyrosine hydroxylase or dopamine-beta-hydroxylase and neuropeptide Y-immunoreactivity were particularly numerous in both organs. Substance P, vasoactive intestinal polypeptide and Leu5-enkephalin-containing nerves were less numerous whereas somatostatin and calcitonin gene-related peptide-immunoreactive nerves occurred occasionally. Bombesin/gastrin-releasing peptide and cholecystokinin immunoreactivities were not present in nervous fibers of the bovine uterus and vagina. Generally, the immunoreactive nerve terminals, fibers, networks or nerve bundles were present below the serous membrane, between smooth muscle cells of muscular layers, around blood vessels, in the submucosal layer and below the luminal epithelium of the uterus and cervix.
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Affiliation(s)
- M Lakomy
- Department of Animal Anatomy, Veterinary Faculty, Olsztyn University of Agriculture and Technology, Olsztyn-Kortowo II, Poland
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26
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Mulder H, Lindh AC, Ekblad E, Westermark P, Sundler F. Islet amyloid polypeptide is expressed in endocrine cells of the gastric mucosa in the rat and mouse. Gastroenterology 1994; 107:712-9. [PMID: 8076756 DOI: 10.1016/0016-5085(94)90118-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BACKGROUND/AIMS Islet amyloid polypeptide (IAPP) or amylin is a novel islet hormone candidate with a suggested role in the regulation of glucose homeostasis and the pathogenesis of non-insulin dependent diabetes mellitus. Occurrence of IAPP in the gastrointestinal tract of rats and humans has also been shown. The expression of IAPP in the stomach of the rat and mouse and the possible colocalization of IAPP and known gastric hormones were investigated in this study. METHODS In situ hybridization, immunofluorescence, and combined in situ hybridization and immunocytochemistry were used. RESULTS IAPP messenger RNA and IAPP-like immunoreactivity were shown in the same endocrine cells in the antrum and fundus of the rat and in the antrum of the mouse. IAPP was expressed in a major population of somatostatin-immunoreactive cells as well as in small populations of gastrin- and peptide YY-immunoreactive cells. CONCLUSIONS Our results establish the synthesis and storage of IAPP in gastric endocrine cells in the rat and mouse. The extensive colocalization of IAPP with somatostatin and to a lesser extent with gastrin and peptide YY suggests that IAPP may modulate endocrine activity in the gastric mucosa in a paracrine and/or autocrine mode.
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Affiliation(s)
- H Mulder
- Department of Medical Cell Research, University of Lund, Sweden
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Abstract
In recent years, studies have suggested that the complexity of eukaryotic gene regulation, with its recurring and interacting motifs of cis and trans-acting regulatory elements, might result in superfluous gene expression. This conclusion is supported by a variety of experimental results that suggest that non-adaptive gene expression might be common. However, with few exceptions, the practical ramifications of unnecessary gene expression for cell biologists have not been addressed directly; this is particularly true for peptidergic neurophysiology, a field that might be plagued more than most with the consequences of this phenomenon. In this article, Chauncey W. Bowers discusses the superfluous expression of neuropeptides in the nervous system in the context of gene regulation extrapolated from studies in Drosophila.
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Affiliation(s)
- C W Bowers
- Division of Neurosciences, Beckman Research Institute, City of Hope, Duarte, CA 91010
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De Giorgio R, Parodi JE, Brecha NC, Brunicardi FC, Becker JM, Go VL, Sternini C. Nitric oxide producing neurons in the monkey and human digestive system. J Comp Neurol 1994; 342:619-27. [PMID: 8040367 DOI: 10.1002/cne.903420409] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Nitric oxide has been proposed as an inhibitory transmitter molecule that plays a role in muscle relaxation and vasodilation in the gastrointestinal tract. The present study analyzes the distribution of nitric-oxide-producing neurons in the monkey and human digestive system by means of nicotinamide-adenine-dinucleotide-phosphate-diaphorase histochemistry. This histochemical method is reliable and convenient for the visualization of neuronal nitric-oxide synthase, the enzyme responsible for nitric-oxide generation. In the gastrointestinal tract, nitric-oxide-synthase-related diaphorase activity was present in nerve fibers running throughout the muscular layer (circular > longitudinal) and in numerous ganglion cells and processes in the myenteric plexus of monkeys and humans. Labelled ganglion cells and fibers also were observed in the submucous plexus, although they were much less numerous than those seen in the myenteric plexus. In the submucosa, a few positive fibers were seen around blood vessels. In the mucosa, stained fibers were sparse at the base of the villi and crypts, whereas they were quite abundant in the muscularis mucosae, especially in the small intestine and colon. In the gallbladder (human), labelling was found in ganglion cells and processes of the innermost and outermost ganglionated plexuses. Stained fibers also were distributed to the muscular layer and, less abundantly, to the mucosa and vasculature. Labelled fibers were more abundant in the sphincter of Oddi (human) than in the gallbladder. In the monkey and human pancreas, nicotinamide-adenine-dinucleotide-diaphorase staining was seen mainly in ganglion cells and fibers of intrapancreatic ganglia, and in processes running among acini, around ducts and in the stroma. A moderate density of stained fibers also was distributed to the vasculature, whereas the islets showed few positive processes. Finally, double label experiments performed in the pancreas showed that the vast majority of neurons producing nitric oxide are immunoreactive for vasoactive intestinal peptide.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- R De Giorgio
- CURE/UCLA Digestive Diseases Center, UCLA School of Medicine
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Barakat A, Skoglund G, Boissard C, Rosselin G, Marie JC. Calcitonin gene-related peptide and islet amyloid polypeptide stimulate insulin secretion in RINm5F cells through a common receptor coupled to a generation of cAMP. Biosci Rep 1994; 14:1-13. [PMID: 8032004 DOI: 10.1007/bf01901633] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The question as to whether the homologous peptides CGRP and IAPP can regulate insulin secretion in RINm5F cells was addressed. Chicken CGRP displayed a reproducible inhibitory effect on insulin secretion within 0.1 and 1 nM concentrations and a stimulatory effect at higher concentrations. The maximal stimulatory effects on insulin secretion were obtained with 1.0 microM of chicken CGRP (cCGRP), human alpha-CGRP (h alpha-CGRP) and human IAPP (hIAPP) which caused 246 +/- 22, 302 +/- 63 and 224 +/- 14 percent increases of control levels, respectively (p < 0.001). Similarly, maximal accumulations of cAMP were obtained with 1.0 microM of cCGRP, h alpha-CGRP and hIAPP with the respective percent increases of control levels of 587 +/- 24, 436 +/- 41 and 410 +/- 25 (p < 0.005). Thus the stimulatory effects on insulin secretion in RINm5F cells by cCGRP, h alpha-CGRP and hIAPP appear to be mediated by the cAMP pathway. Chicken CGRP, the most potent peptide tested, displayed a correlated dose response stimulation of intracellular cAMP and insulin release within the concentration range of 10-1000nM. The EC50 values of cCGRP for cAMP accumulation and insulin release were similar (20nM and 10nM respectively). The stimulatory effect of IAPP on cAMP was not additive with that of cCGRP suggesting that IAPP action was mediated by CGRP receptors. This hypothesis was further sustained by a preferential inhibition of 125I[His]h alpha-CGRP binding to RINm5F cells by cCGRP as compared to IAPP. We conclude that CGRP and IAPP, through a direct action on a chicken CGRP preferring receptor present in beta cells, stimulated insulin by a cAMP mediated pathway.
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Affiliation(s)
- A Barakat
- Institut National de la Santé et de la Recherche Médicale U.55, Hôpital Saint-Antoine, Paris, France
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Mulder H, Lindh AC, Sundler F. Islet amyloid polypeptide gene expression in the endocrine pancreas of the rat: a combined in situ hybridization and immunocytochemical study. Cell Tissue Res 1993; 274:467-74. [PMID: 7904897 DOI: 10.1007/bf00314543] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The expression of the islet amyloid polypeptide (IAPP) gene within the endocrine pancreas and its correlation with insular neuroendocrine peptide localization were investigated in the rat. In situ hybridization with a 35S-labelled IAPP-mRNA specific oligonucleotide probe was combined with immunocytochemistry. In situ hybridization alone showed strong autoradiographic labelling of the pancreatic islets. In situ hybridization combined with immunocytochemistry for IAPP, revealed labelling of the IAPP-immunoreactive cells. However, when in situ hybridization was combined with immunocytochemistry for proinsulin, we noted a lack of proinsulin immunoreactivity in some peripherally located autoradiographically labelled islet cells. Furthermore, combination of in situ hybridization and immunocytochemistry for somatostatin showed autoradiographic labelling of somatostatin cells to a varying degree. This was further confirmed by showing cellular co-localization of IAPP and somatostatin by immunocytochemical double staining. We conclude that IAPP is mainly synthesized in insulin cells. Additionally, a subpopulation of the somatostatin cells is capable of IAPP synthesis. This may account for the relatively small reduction in the content of IAPP-mRNA in islets compared to the marked reduction of insulin mRNA after streptozotocin-induced diabetes in rats as previously reported.
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Affiliation(s)
- H Mulder
- Department of Medical Cell Research, University of Lund, Sweden
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Sternini C, De Giorgio R, Furness JB. Calcitonin gene-related peptide neurons innervating the canine digestive system. REGULATORY PEPTIDES 1992; 42:15-26. [PMID: 1475404 DOI: 10.1016/0167-0115(92)90020-u] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pattern of nerve cells and fibers containing calcitonin gene-related peptide immunoreactivity (CGRP-IR) was investigated in the canine digestive tract by means of immunohistochemistry. CGRP-IR nerve fibers innervate all the layers of the gut, including the vasculature, with different densities depending on the region. CGRP-IR processes are sparse in the esophagus and stomach, where they are mostly confined to the enteric plexuses and vasculature. CGRP-IR fibers are quite abundant in the small and large intestine, where they form dense arborizations in the mucosa, and are numerous in the muscularis mucosae, deep muscular plexus and circular muscle. The myenteric and submucous plexuses of the intestine contain dense networks of CGRP-IR fibers and numerous CGRP-IR ganglion cells. On the other hand, in the enteric ganglia of the esophagus and stomach, in the intrapancreatic ganglia and in the ganglionated plexus of the gallbladder, CGRP-IR is restricted to non-varicose processes. A moderate density of CGRP-IR fibers supplies the endocrine and exocrine pancreas, and the fibromuscular layer and lamina propria of the gallbladder. The density of CGRP innervation in different regions can be summarized as follows: intestine >> pancreas and gallbladder > or = antrum > cardia > gastric corpus and distal esophagus. CGRP- and tachykinin (TK)-IRs are colocalized in a substantial population of fibers, particularly those distributed to the mucosa, muscularis mucosae and vasculature, whereas there was no evidence of colocalization in intrinsic ganglion cells. The present results suggest that (1) the CGRP innervation of the dog digestive system includes an intrinsic and an extrinsic component, and (2) CGRP- and TK-IRs are co-expressed in extrinsic nerve fibers. These findings extend previous observations in rats and guinea pigs and provide insights into the sites of action of CGRP in the digestive system of the dog, which has served as a model for CGRP functional studies.
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Affiliation(s)
- C Sternini
- Department of Medicine, UCLA School of Medicine
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