1
|
Botros M, Alsaghayer A, Tanabe C, Armas K, Mabry M, Goodarzi A, Yau S, Youssef J, Huang H, Ren D, Suarez E. Extending Cold Ischemic Time Using LUNGguard: A Single Center Experience in Time Shifting. J Heart Lung Transplant 2023. [DOI: 10.1016/j.healun.2023.02.1442] [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: 04/05/2023] Open
|
2
|
Botros M, Ziada EAA, El-Kalla IL. Semi-analytic solutions of nonlinear multidimensional fractional differential equations. Math Biosci Eng 2022; 19:13306-13320. [PMID: 36654048 DOI: 10.3934/mbe.2022623] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
In this paper, the Adomian decomposition method (ADM) and Picard technique are used to solve a class of nonlinear multidimensional fractional differential equations with Caputo-Fabrizio fractional derivative. The main advantage of the Caputo-Fabrizio fractional derivative appears in its non-singular kernel of a convolution type. The sufficient condition that guarantees a unique solution is obtained, the convergence of the series solution is discussed, and the maximum absolute error is estimated. Several numerical problems with an unknown exact solution are solved using the two techniques. A comparative study between the two solutions is presented. A comparative study shows that the time consumed by ADM is much smaller compared with the Picard technique.
Collapse
Affiliation(s)
- M Botros
- Basic Science Departement, Faculty of Engineering, Delta Universiry for Science and Technology, P. O. Box 11152, Mansoura, Egypt
| | - E A A Ziada
- Nile Higher Institute for Engineering and Technology, Mansoura, Egypt
| | - I L El-Kalla
- Mathematics and Engineering Physics Department, Faculty of Engineering, Mansoura University, Mansoura, Egypt
| |
Collapse
|
3
|
Botros M, Rosenheck J, Sulejmani N, Keller B. Donor-Derived Cell-Free DNA Plus Tissue Gene Expression Profiling of Lung Allograft Injury. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.172] [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: 10/18/2022] Open
|
4
|
Rosenheck J, Ross D, Botros M, Wong A, Chen Y, Van Hummelen P, Keller B. Quantitative Donor-Derived Cell-Free DNA Levels Reflect the Variability in Lung Allograft Cellular Injury. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.171] [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: 11/24/2022] Open
|
5
|
Rosenheck J, Ross D, Wong A, Botros M, Haque N, Van Hummelen P, Shih R, Olymbios M, Sternberg J, Keller B. Metagenomic Next Generation Sequencing (mNGS) Can Complement Fractional Donor-Derived Cell-Free DNA in Lung Allograft Assessment: Pilot Data. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.173] [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: 10/18/2022] Open
|
6
|
Wallinder C, Sköld C, Botros M, Guimond MO, Hallberg M, Gallo-Payet N, Karlén A, Alterman M. Interconversion of Functional Activity by Minor Structural Alterations in Nonpeptide AT2 Receptor Ligands. ACS Med Chem Lett 2015; 6:178-82. [PMID: 25699147 DOI: 10.1021/ml500427r] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 12/08/2014] [Indexed: 11/30/2022] Open
Abstract
Migration of the methylene imidazole side chain in the first reported selective drug-like AT2 receptor agonist C21/M024 (1) delivered the AT2 receptor antagonist C38/M132 (2). We now report that the AT2 receptor antagonist compound 4, a biphenyl derivative that is structurally related to 2, is transformed to the agonist 6 by migration of the isobutyl group. The importance of the relative position of the methylene imidazole and the isobutyl substituent is highlighted herein.
Collapse
Affiliation(s)
- Charlotta Wallinder
- Organic Pharmaceutical Chemistry, Department
of Medicinal Chemistry, BMC, Uppsala University, SE-751 23 Uppsala, Sweden
| | - Christian Sköld
- Organic Pharmaceutical Chemistry, Department
of Medicinal Chemistry, BMC, Uppsala University, SE-751 23 Uppsala, Sweden
| | - Milad Botros
- Beijer Laboratory, Department of Pharmaceutical
Biosciences, BMC, Uppsala University SE-751 23 Uppsala, Sweden
| | - Marie-Odile Guimond
- Service of Endocrinology, Faculty of Medicine
and Heath Sciences, University of Sherbrooke, Sherbrooke J1H 5N4, Quebec, Canada
| | - Mathias Hallberg
- Beijer Laboratory, Department of Pharmaceutical
Biosciences, BMC, Uppsala University SE-751 23 Uppsala, Sweden
| | - Nicole Gallo-Payet
- Service of Endocrinology, Faculty of Medicine
and Heath Sciences, University of Sherbrooke, Sherbrooke J1H 5N4, Quebec, Canada
| | - Anders Karlén
- Organic Pharmaceutical Chemistry, Department
of Medicinal Chemistry, BMC, Uppsala University, SE-751 23 Uppsala, Sweden
| | - Mathias Alterman
- Organic Pharmaceutical Chemistry, Department
of Medicinal Chemistry, BMC, Uppsala University, SE-751 23 Uppsala, Sweden
| |
Collapse
|
7
|
Chen X, Botros M, Ahunbay E, Wang D, Schultz C, Li X. SU-F-BRF-15: Interfractional Dose Variations in Parotid and Submandibular Glands in IG-IMRT for Head and Neck Cancer. Med Phys 2014. [DOI: 10.1118/1.4889084] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
|
8
|
Prior P, Botros M, Chen X, Paulson E, Erickson B, Li X. SU-E-J-193: Feasibility of MRI-Only Based IMRT Planning for Pancreatic Cancer. Med Phys 2014. [DOI: 10.1118/1.4888246] [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: 11/07/2022] Open
|
9
|
Stauder MC, Romero Y, Kabat B, Atherton PJ, Geno D, Deschamps C, Jatoi A, Sloan JA, Botros M, Jung KW, Arora AS, Miller RC. Overall survival and self-reported fatigue in patients with esophageal cancer. Support Care Cancer 2012; 21:511-9. [DOI: 10.1007/s00520-012-1537-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Accepted: 06/25/2012] [Indexed: 11/12/2022]
|
10
|
Murugaiah AMS, Wu X, Wallinder C, Mahalingam AK, Wan Y, Sköld C, Botros M, Guimond MO, Joshi A, Nyberg F, Gallo-Payet N, Hallberg A, Alterman M. From the first selective non-peptide AT(2) receptor agonist to structurally related antagonists. J Med Chem 2012; 55:2265-78. [PMID: 22248302 DOI: 10.1021/jm2015099] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A para substitution pattern of the phenyl ring is a characteristic feature of the first reported selective AT(2) receptor agonist M024/C21 (1) and all the nonpeptidic AT(2) receptor agonists described so far. Two series of compounds structurally related to 1 but with a meta substitution pattern have now been synthesized and biologically evaluated for their affinity to the AT(1) and AT(2) receptors. A high AT(2)/AT(1) receptor selectivity was obtained with all 41 compounds synthesized, and the majority exhibited K(i) ranging from 2 to 100 nM. Five compounds were evaluated for their functional activity at the AT(2) receptor, applying a neurite outgrowth assay in NG108-15 cells. Notably, four of the five compounds, with representatives from both series, acted as potent AT(2) receptor antagonists. These compounds were found to be considerably more effective than PD 123,319, the standard AT(2) receptor antagonist used in most laboratories. No AT(2) receptor antagonists were previously reported among the derivatives with a para substitution pattern. Hence, by a minor modification of the agonist 1 it could be transformed into the antagonist, compound 38. These compounds should serve as valuable tools in the assessment of the role of the AT(2) receptor in more complex physiological models.
Collapse
Affiliation(s)
- A M S Murugaiah
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Stauder MC, Romero Y, Kabat B, Atherton PJ, Fredericksen MB, Deschamps C, Jatoi A, Sloan JA, Botros M, Miller RC. Analysis of overall survival and self-reported fatigue in patients with locally advanced esophageal cancer: A Mayo Clinic Esophageal Adenocarcinoma and Barrett’s Esophagus Registry Consortium study. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.9057] [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: 11/20/2022] Open
|
12
|
Stauder MC, Romero Y, Kabat B, Atherton PJ, Fredericksen MB, Deschamps C, Jatoi A, Sloan JA, Botros M, Miller RC. Patient-reported fatigue and overall survival in locally advanced esophageal cancer: A Mayo Clinic Esophageal Adenocarcinoma and Barrett's Esophagus Registry Consortium study. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.4_suppl.9] [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: 11/20/2022] Open
Abstract
9 Background: We examined patient-reported fatigue scores and overall survival (OS) in patients with esophageal cancer (EC) enrolled in the Mayo Clinic Esophageal Adenocarcinoma and Barrett's Esophagus Registry (EABE). Methods: 1,481 patients enrolled in the EABE between September 2001 and January 2009 returned a baseline quality of life questionnaire including a Linear Analog Self Assessment (LASA) fatigue score which was scored on a 0-10 scale, with 0 as the most extreme fatigue. Patients were categorized as having clinically deficient fatigue (DF) if they reported a score of ≤ 5 and clinically non-deficient fatigue (nDF) if they reported a score of > 5. Kaplan-Meier methodology and Cox models explored OS in relation to fatigue scores in patients with EC. Results: A total of 667 patients with EC were included in the EABE, of which 659 returned a registry questionnaire with a valid LASA fatigue score recorded. Median age at the time of registry entry was 65 years (range 23-92). A total of 392 (59%) and 267 patients (41%) reported DF and nDF, respectively. On univariate analysis, patients with nDF had improved 5-year survival compared to patients with DF. In patients having esophagectomy prior to LASA, those reporting nDF had improved survival compared to patients with DF. Similarly, in patients having no esophagectomy prior to LASA, those with nDF had improved survival compared to those with DF. Among the 368 patients with locally advanced EC (LAEC), those reporting nDF had improved 5-year overall survival compared to patients with DF (28% vs 17%, HR = 0.67, p = 0.003). This remained significant on multivariate analysis (HR = 0.71, p = 0.015). Conclusions: Patient-reported fatigue is associated with overall survival in patients with LAEC. As a result, fatigue scores should be considered as a stratification factor in future clinical trial design. [Table: see text] No significant financial relationships to disclose.
Collapse
|
13
|
Botros M, Lu Z, Sikaris K. Using clinical notes provided on request forms to assess the risk associated with isolated ureamia. Pathology 2011. [DOI: 10.1016/s0031-3025(16)33209-3] [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: 10/22/2022]
|
14
|
Botros M, Lu Z, Sikaris K. Using clinical notes provided on request forms to assess the risk associated with isolated ureamia. Pathology 2011. [DOI: 10.1016/s0031-3025(16)33192-0] [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: 12/01/2022]
|
15
|
Fransson R, Botros M, Sköld C, Nyberg F, Lindeberg G, Hallberg M, Sandström A. Discovery of dipeptides with high affinity to the specific binding site for substance P1-7. J Med Chem 2010; 53:2383-9. [PMID: 20178322 DOI: 10.1021/jm901352b] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Substance P 1-7 (SP(1-7), H-Arg-Pro-Lys-Pro-Gln-Gln-Phe-OH) is the major bioactive metabolite of substance P. The interest in this heptapeptide originates from the observation that it modulates, and in certain cases opposes the effects of the parent peptide, e.g., the nociceptive effect. The mu-opioid receptor agonist endomorphin-2 (EM-2, H-Tyr-Pro-Phe-Phe-NH(2)) has been found to also interact with the specific binding site of SP(1-7) with only a 10-fold lower affinity compared to the native peptide. Considering the smaller size of EM-2 compared to the target heptapeptide, it was selected as a lead compound in the development of low-molecular-weight ligands to the SP(1-7) binding site. An alanine scan and truncation study led to the unexpected discovery of the dipeptide H-Phe-Phe-NH(2) (K(i) = 1.5 nM), having equal affinity as the endogenous heptapeptide SP(1-7.) Moreover, the studies show that the C-terminal phenylalanine amide is crucial for the affinity of the dipeptide.
Collapse
Affiliation(s)
- Rebecca Fransson
- Department of Medicinal Chemistry, Uppsala University, Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | |
Collapse
|
16
|
Zhou Q, Carlsson A, Botros M, Fransson R, Sandström A, Gordh T, Hallberg M, Nyberg F. The C-terminal amidated analogue of the substance P (SP) fragment SP(1-7) attenuates the expression of naloxone-precipitated withdrawal in morphine dependent rats. Peptides 2009; 30:2418-22. [PMID: 19686790 DOI: 10.1016/j.peptides.2009.08.009] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [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] [Received: 07/12/2009] [Revised: 08/07/2009] [Accepted: 08/07/2009] [Indexed: 11/15/2022]
Abstract
We previously demonstrated that intracerebroventricular (i.c.v.) administration of the substance P (SP) aminoterminal fragment SP(1-7) attenuates the expression of morphine withdrawal in the male rat. In this study we have used a synthetic analogue of this peptide, i.e. the SP(1-7) amide showing higher binding potency than the native heptapeptide, in a similar experimental set-up. Thus, Wistar male rats were made tolerant to morphine by daily injections of the opiate during 8 days. Following peptide administration (i.c.v.) and a subsequent naloxone challenge a variety of physical syndromes of withdrawal were recorded. We observed that the SP(1-7) amide potently and dose-dependently reduced several signs of reaction to morphine withdrawal. Interestingly, the effect of the peptide amide was significantly attenuated by the addition of the sigma agonist (+)-SKF-10047. We conclude that the SP(1-7) amide mimics the effect of the native SP fragment and that the mechanisms for its action involve a sigma receptor site.
Collapse
Affiliation(s)
- Qin Zhou
- Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, S-751 24 Uppsala, Sweden
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Botros M, Johansson T, Zhou Q, Lindeberg G, Tömböly C, Tóth G, Le Grevès P, Nyberg F, Hallberg M. Endomorphins interact with the substance P (SP) aminoterminal SP(1-7) binding in the ventral tegmental area of the rat brain. Peptides 2008; 29:1820-4. [PMID: 18597894 DOI: 10.1016/j.peptides.2008.05.014] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [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] [Received: 01/09/2008] [Revised: 05/15/2008] [Accepted: 05/17/2008] [Indexed: 10/22/2022]
Abstract
We have recently identified a specific binding site for the tachykinin peptide substance P (SP) fragment SP(1-7) in the rat spinal cord. This site appeared very specific for SP(1-7) as the binding affinity of this compound highly exceeded those of other SP fragments. We also observed that endomorphin-2 (EM-2) exhibited high potency in displacing SP(1-7) from this site. In the present work using a [(3)H]-labeled derivative of the heptapeptide we have identified and characterized [(3)H]-SP(1-7) binding in the rat ventral tegmental area (VTA). Similarly to the [(3)H]-SP(1-7) binding in the spinal cord the affinity of unlabeled SP(1-7) to the specific site in VTA was significantly higher than those of other SP fragments. Further, the tachykinin receptor NK-1, NK-2 and NK-3 ligands showed no or negligible binding to the identified site. However, the mu-opioid peptide (MOP) receptor agonists DAMGO, EM-1 and EM-2 did, and significant difference was observed in the binding affinity between the two endomorphins. As recorded from displacement curves the affinity of EM-2 for the SP(1-7) site was 4-5 times weaker than that for SP(1-7) but about 5 times higher than that of EM-1. The opioid receptor antagonists naloxone and naloxonazine showed weak or negligible binding. It was concluded that the specific site identified for SP(1-7) binding in the rat VTA is distinct from the MOP receptor although it exhibits high affinity for EM-2.
Collapse
Affiliation(s)
- Milad Botros
- Department of Pharmaceutical Biosciences, Uppsala University, SE-751 24 Uppsala, Sweden
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Wallinder C, Botros M, Rosenström U, Guimond MO, Beaudry H, Nyberg F, Gallo-Payet N, Hallberg A, Alterman M. Erratum to “Selective angiotensin II AT2 receptor agonists: Benzamide structure–activity relationships” [Bioorg. Med. Chem. 16 (2008) 6841–6849]. Bioorg Med Chem 2008. [DOI: 10.1016/j.bmc.2008.08.045] [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: 11/25/2022]
|
19
|
Fransson R, Botros M, Nyberg F, Lindeberg G, Sandström A, Hallberg M. Small peptides mimicking substance P (1-7) and encompassing a C-terminal amide functionality. Neuropeptides 2008; 42:31-7. [PMID: 18093649 DOI: 10.1016/j.npep.2007.11.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [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] [Received: 07/08/2007] [Revised: 10/22/2007] [Accepted: 11/09/2007] [Indexed: 11/28/2022]
Abstract
Some of the biological effects demonstrated after administration of substance P (SP) in vivo can indirectly be attributed to the fragmentation of the undecapeptide to its N-terminal bioactive fragment SP(1-7). This heptapeptide (H-Arg-Pro-Lys-Pro-Gln-Gln-Phe-OH) is a major bioactive metabolite from SP that frequently exerts similar biological effects as the parent peptide but also, in several cases, completely opposite actions. Specific binding sites for the heptapeptide SP(1-7) that are separate from the SP preferred NK receptors have been identified. In this study we demonstrate that (a) the C-terminal part of the SP metabolite SP(1-7) is most important for binding as deduced from an Ala scan and that a replacement of Phe(7) for Ala is deleterious, (b) truncation of the N-terminal amino acid residues of SP(1-7) delivers peptides with retained binding activity, although with somewhat lower binding affinities than SP(1-7) and (c) a C-terminal amide group as a replacement for the terminal carboxy group of SP(1-7) and for all of the truncated ligands synthesized affords approximately 5-10-fold improvements of the binding affinities.
Collapse
Affiliation(s)
- Rebecca Fransson
- Department of Medicinal Chemistry, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | |
Collapse
|
20
|
Murugaiah AMS, Wallinder C, Mahalingam AK, Wu X, Wan Y, Plouffe B, Botros M, Karlén A, Hallberg M, Gallo-Payet N, Alterman M. Selective angiotensin II AT2 receptor agonists devoid of the imidazole ring system. Bioorg Med Chem 2007; 15:7166-83. [PMID: 17825570 DOI: 10.1016/j.bmc.2007.07.026] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 06/28/2007] [Accepted: 07/06/2007] [Indexed: 11/19/2022]
Abstract
A versatile parallel synthetic method to obtain three series of non-cyclic analogues of the first drug-like selective angiotensin II AT(2) receptor agonist (1) has been developed. In analogy with the transformation of losartan to valsartan it was demonstrated that a non-cyclic moiety could be employed as an imidazole replacement to obtain AT(2) selective compounds. In all the three series, AT(2) receptor ligands with affinities in the lower nanomolar range were found. None of the analogues exhibited any affinity for the AT(1) receptor. Four compounds, 17, 22, 39 and 51, were examined in a neurite outgrowth cell assay. All four compounds were found to exert a high agonistic effect as deduced from their capacity to induce neurite elongation in neuronal cells, as does angiotensin II.
Collapse
Affiliation(s)
- A M S Murugaiah
- Department of Medicinal Chemistry, BMC, Uppsala University, PO Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Georgsson J, Sköld C, Botros M, Lindeberg G, Nyberg F, Karlén A, Hallberg A, Larhed M. Synthesis of a new class of druglike angiotensin II C-terminal mimics with affinity for the AT2 receptor. J Med Chem 2007; 50:1711-5. [PMID: 17358051 DOI: 10.1021/jm0613469] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [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: 11/28/2022]
Abstract
Four tripeptides corresponding to the C-terminal region of angiotensin II were synthesized. One of these peptides (Ac-His-Pro-Ile) showed moderate binding affinity for the AT2 receptor. Two aromatic histidine-related scaffolds were synthesized and introduced in the tripeptides to give eight new peptidomimetic structures. Three of the new peptide-derived druglike molecules exhibited selective, nanomolar affinity for the AT2 receptor. These ligands may become lead compounds in the future development of novel classes of selective AT2 receptor agonists.
Collapse
Affiliation(s)
- Jennie Georgsson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Wu X, Wan Y, Mahalingam AK, Murugaiah AMS, Plouffe B, Botros M, Karlén A, Hallberg M, Gallo-Payet N, Alterman M. Selective Angiotensin II AT2 Receptor Agonists: Arylbenzylimidazole Structure−Activity Relationships. J Med Chem 2006; 49:7160-8. [PMID: 17125268 DOI: 10.1021/jm0606185] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [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: 11/30/2022]
Abstract
Structural alterations in the 2- and 5-positions of the first drug-like selective angiotensin II AT2 receptor agonist (1) have been performed. The imidazole ring system was proven to be a strong determinant for the AT2 selectivity, and with few exceptions all variations gave good AT2 receptor affinities and with retained high AT2/AT1 selectivities. On the contrary to the findings with AT1 receptor agonists, the impact of structural modifications in the 5-position of the AT2 selective compounds were less pronounced regarding activation of the AT2 receptor. The butyloxyphenyl (56) and the propylthienyl (50) derivatives were found to exert a high agonistic effect as deduced from their capacity to induce neurite elongation in neuronal cells, as does angiotensin II.
Collapse
Affiliation(s)
- Xiongyu Wu
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Rosenström U, Sköld C, Lindeberg G, Botros M, Nyberg F, Karlén A, Hallberg A. Design, Synthesis, and Incorporation of a β-Turn Mimetic in Angiotensin II Forming Novel Pseudopeptides with Affinity for AT1 and AT2 Receptors. J Med Chem 2006; 49:6133-7. [PMID: 17004728 DOI: 10.1021/jm051222g] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [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: 11/29/2022]
Abstract
A benzodiazepine-based beta-turn mimetic has been designed, synthesized, and incorporated into angiotensin II. Comparison of the mimetic with beta-turns in crystallized proteins showed that it most closely resembles a type II beta-turn. The compounds exhibited high to moderate binding affinity for the AT2 receptor, and one also displayed high affinity for the AT1 receptor. Molecular modeling showed that the high-affinity compounds could be incorporated into a previously derived model of AT2 receptor ligands.
Collapse
MESH Headings
- Angiotensin II/chemistry
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiology
- Benzodiazepines/chemical synthesis
- Benzodiazepines/chemistry
- Benzodiazepines/pharmacology
- Drug Design
- Female
- In Vitro Techniques
- Ligands
- Liver/drug effects
- Liver/metabolism
- Models, Molecular
- Molecular Mimicry
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Peptides/chemistry
- Protein Structure, Secondary
- Rabbits
- Radioligand Assay
- Rats
- Receptor, Angiotensin, Type 1/agonists
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 2/agonists
- Receptor, Angiotensin, Type 2/metabolism
- Swine
- Uterus/drug effects
- Uterus/metabolism
Collapse
Affiliation(s)
- Ulrika Rosenström
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | |
Collapse
|
24
|
Georgsson J, Rosenström U, Wallinder C, Beaudry H, Plouffe B, Lindeberg G, Botros M, Nyberg F, Karlén A, Gallo-Payet N, Hallberg A. Short pseudopeptides containing turn scaffolds with high AT2 receptor affinity. Bioorg Med Chem 2006; 14:5963-72. [PMID: 16753301 DOI: 10.1016/j.bmc.2006.05.019] [Citation(s) in RCA: 17] [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] [Received: 12/19/2005] [Revised: 05/04/2006] [Accepted: 05/15/2006] [Indexed: 11/22/2022]
Abstract
Two pentapeptides, Ac-Tyr-Ile-His-Pro-Phe/Ile, were synthesized and shown to have angiotensin II AT2 receptor affinity and agonistic activity. Based on these peptides, a new series of 13 pseudopeptides was synthesized via introduction of five different turn scaffolds replacing the Tyr-Ile amino acid residues. Pharmacological evaluation disclosed subnanomolar affinities for some of these compounds at the AT2 receptor. Substitution of Phe by Ile in this series of ligands enhanced the AT2 receptor affinity of all compounds. These results suggest that the C-terminal amino acid residues can be elaborated on to enhance the AT2 receptor affinity in truncated Ang II analogues.
Collapse
Affiliation(s)
- Jennie Georgsson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, PO Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
25
|
Botros M, Hallberg M, Johansson T, Zhou Q, Lindeberg G, Frändberg PA, Tömböly C, Tóth G, Le Grevès P, Nyberg F. Endomorphin-1 and endomorphin-2 differentially interact with specific binding sites for substance P (SP) aminoterminal SP1-7 in the rat spinal cord. Peptides 2006; 27:753-9. [PMID: 16216386 DOI: 10.1016/j.peptides.2005.08.009] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [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] [Received: 07/19/2005] [Revised: 08/18/2005] [Accepted: 08/18/2005] [Indexed: 10/25/2022]
Abstract
Endomorphin-1 (EM-1) and endomorphin-2 (EM-2) represent two opioid active tetrapeptides with high affinity and selectivity for the mu-opioid (MOP) receptor. Both EM-1 and EM-2 exhibit strong inhibition of pain signals in the central nervous system (CNS). In contrast to these compounds, the undecapeptide substance P (SP) facilitates pain influx in the CNS. SP has been implicated in a number of functions in the central nervous system, including pain processing and reward. Its aminoterminal fragment SP1-7 has been shown to modulate several actions of SP in the CNS, the nociceptive effect included. Although the actions of SP1-7 have been known for long no specific receptor for the SP fragment has yet been cloned. In this study, we demonstrate the presence of specific binding sites for the heptapeptide in the rat spinal cord. The binding affinity for unlabeled SP1-7 to the specific sites for the labeled heptapeptide highly exceeded those of SP and other C- or N-terminal fragments thereof. The NK-1, NK-2 and NK-3 receptor ligands [Sar9, Met(O2)11]SP, R396 and senktide, respectively, showed no or negligible binding. Moreover, both EM-1 and EM-2 were found to interact with SP1-7 binding. However, a significant difference in binding affinity between the two opioid active tetrapeptides was observed. As recorded from replacement curves the affinity of EM-2 was 10 times weaker than that for SP1-7 but about 100 times higher than that of EM-1. Among other Tyr-Pro-containing peptides Tyr-MIF-1 but not Tyr-W-MIF-1 exhibited affinity of similar potency as EM-2. These results strengthen the previously observed differences between EM-1 and EM-2 in various functional studies. Moreover, using a cell line (C6) expressing the MOP receptor it was shown that the labeled SP1-7 did not interact with binding to this receptor and no functional response was seen for the SP heptapeptide on the MOP receptor by means of stimulation in the GTPgammaS assay. This suggests that the identified SP1-7 binding sites, with high affinity also for EM-2, are not identical to the MOP receptor and apparently not to any of the known tachykinin receptors.
Collapse
Affiliation(s)
- Milad Botros
- Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, BMC, Box 591, SE-751 24 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Georgsson J, Sköld C, Plouffe B, Lindeberg G, Botros M, Larhed M, Nyberg F, Gallo-Payet N, Gogoll A, Karlén A, Hallberg A. Angiotensin II pseudopeptides containing 1,3,5-trisubstituted benzene scaffolds with high AT2 receptor affinity. J Med Chem 2005; 48:6620-31. [PMID: 16220978 DOI: 10.1021/jm050280z] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [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: 11/28/2022]
Abstract
Two 1,3,5-trisubstituted aromatic scaffolds intended to serve as gamma-turn mimetics have been synthesized and incorporated in five pseudopeptide analogues of angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe), replacing Val-Tyr-Ile, Val-Tyr, or Tyr-Ile. All the tested compounds exhibited nanomolar affinity for the AT2 receptor with the best compound (3) having a K(i) of 1.85 nM. Four pseudopeptides were AT2 selective, while one (5) also exhibited good affinity for the AT1 receptor (K(i) = 30.3 nM). This pseudopeptide exerted full agonistic activity in an AT2 receptor induced neurite outgrowth assay but displayed no agonistic effect in an AT1 receptor functional assay. Molecular modeling, using the program DISCOtech, showed that the high-affinity ligands could interact similarly with the AT2 receptor as other ligands with high affinity for this receptor. A tentative agonist model is proposed for AT2 receptor activation by angiotensin II analogues. We conclude that the 1,3,5-trisubstituted benzene rings can be conveniently prepared and are suitable as gamma-turn mimics.
Collapse
MESH Headings
- Angiotensin II/analogs & derivatives
- Angiotensin II/chemical synthesis
- Angiotensin II/pharmacology
- Animals
- Aorta, Thoracic/drug effects
- Aorta, Thoracic/physiology
- Benzene Derivatives/chemical synthesis
- Benzene Derivatives/pharmacology
- Cell Line, Tumor
- Female
- In Vitro Techniques
- Ligands
- Liver/metabolism
- Models, Molecular
- Molecular Mimicry
- Muscle Contraction/drug effects
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Myometrium/metabolism
- Neurites/drug effects
- Neurites/physiology
- Oligopeptides/chemical synthesis
- Oligopeptides/pharmacology
- Protein Structure, Secondary
- Rabbits
- Radioligand Assay
- Rats
- Receptor, Angiotensin, Type 1/agonists
- Receptor, Angiotensin, Type 1/metabolism
- Receptor, Angiotensin, Type 2/agonists
- Receptor, Angiotensin, Type 2/metabolism
- Swine
Collapse
Affiliation(s)
- Jennie Georgsson
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Rosenström U, Sköld C, Plouffe B, Beaudry H, Lindeberg G, Botros M, Nyberg F, Wolf G, Karlén A, Gallo-Payet N, Hallberg A. New selective AT2 receptor ligands encompassing a gamma-turn mimetic replacing the amino acid residues 4-5 of angiotensin II act as agonists. J Med Chem 2005; 48:4009-24. [PMID: 15943474 DOI: 10.1021/jm0491492] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [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: 11/29/2022]
Abstract
New benzodiazepine-based gamma-turn mimetics with one or two amino acid side chains were synthesized. The gamma-turn mimetics were incorporated into angiotensin II (Ang II) replacing the Val(3)-Tyr(4)-Ile(5) or Tyr(4)-Ile(5) peptide segments. All of the resulting pseudopeptides displayed high AT(2)/AT(1) receptor selectivity and exhibited AT(2) receptor affinity in the low nanomolar range. Molecular modeling was used to investigate whether the compounds binding to the AT(2) receptor could position important structural elements in common areas. A previously described benzodiazepine-based gamma-turn mimetic with high affinity for the AT(2) receptor was also included in the modeling. It was found that the molecules, although being structurally quite different, could adopt the same binding mode/interaction pattern in agreement with the model hypothesis. The pseudopeptides selected for agonist studies were shown to act as AT(2) receptor agonists being able to induce outgrowth of neurite cells, stimulate p42/p44(mapk), and suppress proliferation of PC12 cells.
Collapse
|
28
|
Rosenström U, Sköld C, Lindeberg G, Botros M, Nyberg F, Hallberg A, Karlén A. Synthesis and AT2 receptor-binding properties of angiotensin II analogues. ACTA ACUST UNITED AC 2004; 64:194-201. [PMID: 15485557 DOI: 10.1111/j.1399-3011.2004.00184.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [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: 11/30/2022]
Abstract
The present study investigates the importance of the amino acid side chains in the octapeptide angiotensin II (Ang II) for binding to the AT2 receptor. A Gly scan was performed where each amino acid in Ang II was substituted one-by-one with glycine. The resulting set of peptides was tested for affinity to the AT2 receptor (porcine myometrial membranes). For a comparison, the peptides were also tested for affinity to the AT1 receptor (rat liver membranes). Only the substitution of Arg2 reduced affinity to the AT2 receptor considerably (92-fold when compared with Ang II). For the other Gly-substituted analogues the affinity to the AT2 receptor was only moderately affected. To further investigate the role of the Arg2 side chain for receptor binding, we synthesized some N-terminally modified Ang II analogues. According to these studies a positive charge in the N-terminal end of angiotensin III [Ang II (2-8)] is not required for high AT2 receptor affinity but seems to be more important in Ang II. With respect to the AT1 receptor, [Gly2]Ang II and [Gly8]Ang II lacked binding affinity (Ki > 10 microM). Replacement of the Val3 or Ile5 residues with Gly produced only a slight decrease in affinity. Interestingly, substitution of Tyr4 or His6, which are known to be very important for AT1 receptor binding, resulted in only 48 and 14 times reduction in affinity, respectively.
Collapse
Affiliation(s)
- U Rosenström
- Department of Medicinal Chemistry, Division of Organic Pharmaceutical Chemistry, Uppsala University, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | |
Collapse
|
29
|
Rosenström U, Sköld C, Lindeberg G, Botros M, Nyberg F, Karlén A, Hallberg A. A selective AT2 receptor ligand with a gamma-turn-like mimetic replacing the amino acid residues 4-5 of angiotensin II. J Med Chem 2004; 47:859-70. [PMID: 14761188 DOI: 10.1021/jm030921v] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [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: 11/29/2022]
Abstract
Three angiotensin II (Ang II) analogues encompassing a benzodiazepine-based gamma-turn-like scaffold have been synthesized. Evaluation of the compounds in a radioligand binding assay showed that they had no affinity to the rat liver AT(1) receptor. However, one of the compounds displayed considerable affinity to the pig uterus AT(2) receptor (K(i) = 3.0 nM) while the other two lacked affinity to this receptor. It was hypothesized that the reason for the inactivity of one of these analogues to the AT(2) receptor was that the guanidino group of the Arg(2) residue and/or the N-terminal end of the pseudopeptide could not interact optimally with the receptor. To investigate this hypothesis, a conformational analysis was performed and a comparison was carried out with the monocyclic methylenedithioether analogue cyclo(S-CH(2)-S)[Cys(3,5)]Ang II which is known to bind with high affinity to the AT(2) receptor (K(i) = 0.62 nM). This comparison showed that, in the compounds with high AT(2) receptor affinity, the guanidino group of the Arg(2) residue and the N-terminal end could access common regions of space that were not accessible to the inactive compound. To examine the importance of the guanidino group for binding, the Arg side chain was removed by substituting Arg(2) for Ala(2) in the analogue having the high affinity. This analogue lacked affinity to AT(2) receptors, which supports the role of the guanidino group in receptor binding.
Collapse
Affiliation(s)
- Ulrika Rosenström
- Division of Organic Pharmaceutical Chemistry, Department of Medicinal Chemistry, BMC, Box 574, Uppsala University, SE-751 23 Uppsala, Sweden
| | | | | | | | | | | | | |
Collapse
|
30
|
Wan Y, Wallinder C, Johansson B, Holm M, Mahalingam AK, Wu X, Botros M, Karlén A, Pettersson A, Nyberg F, Fändriks L, Hallberg A, Alterman M. First Reported Nonpeptide AT1Receptor Agonist (L-162,313) Acts as an AT2Receptor Agonist in Vivo. J Med Chem 2004; 47:1536-46. [PMID: 14998339 DOI: 10.1021/jm031031i] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [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: 11/29/2022]
Abstract
In this investigation, it is demonstrated that the first nonpeptide AT(1) receptor agonist L-162,313 (1), disclosed in 1994, also acts as an agonist at the AT(2) receptor. In anesthetized rats, administration of compound 1 intravenously or locally in the duodenum increased duodenal mucosal alkaline secretion, effects that were sensitive to the selective AT(2) receptor antagonist PD-123,319. The data strongly suggest that 1 is an AT(2) receptor agonist in vivo. To the best of our knowledge, this substance is the first nonpeptidic low-molecular weight compound with an agonistic effect mediated through the AT(2) receptor.
Collapse
Affiliation(s)
- Yiqian Wan
- Department of Medicinal Chemistry, BMC, Uppsala University, P.O. Box 574, SE-751 23 Uppsala, Sweden.
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Adem A, Synnergren B, Botros M, Ohman B, Winblad B, Nordberg A. [3H]acetylcholine nicotinic recognition sites in human brain: characterization of agonist binding. Neurosci Lett 1987; 83:298-302. [PMID: 3441312 DOI: 10.1016/0304-3940(87)90103-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [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: 01/05/2023]
Abstract
In the presence of a cholinesterase inhibitor to prevent hydrolysis and atropine to block muscarinic cholinergic receptors, [3H]acetylcholine ([3H]ACh) binding to human brain membranes showed highest levels of nicotinic binding sites in the thalamus. [3H]ACh, in the presence of atropine, binds to heterogeneous high-affinity binding sites in human thalamus. Scatchard analysis of the binding gave a Kd of 0.58 nM and a Bmax of 3.3 pmol/g protein for the 'super high-affinity' site and a Kd of 27 nM and a Bmax of 70 pmol/g protein for the 'high-affinity' site. Moreover, in competition studies nicotinic agonists such (-)-nicotine and carbachol displaceable [3H]ACh-specific binding sites consist of both a high- and a low-affinity population of sites. These results indicate that highest levels of [3H]ACh binding in human brain were found in the thalamus. Moreover, the human thalamus was found to have multiple high-affinity nicotinic agonist sites.
Collapse
Affiliation(s)
- A Adem
- Department of Pharmacology, University of Uppsala, Sweden
| | | | | | | | | | | |
Collapse
|
32
|
Radwan M, Massoud AA, Botros M, Ali MA. Epidemiologic study of type II diabetes associated vascular complications. J Med Assoc Thai 1987; 70 Suppl 2:190-3. [PMID: 3598430] [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: 01/06/2023]
|
33
|
Botros M, Selim R, Ghoneim K, Ghareeb A, Wahba N. Insulinotrophic drugs. Effect on intestinal abosorption of sugar. Diabetes 1974; 23:112-6. [PMID: 4204422 DOI: 10.2337/diab.23.2.112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The effect of some insulinotrophic drugs on the transport of sugar was investigated in fasted, narcotized rats by continuous perfusion of cannulated long intestinal loops with galactose solution (18 mM.) circulated by air lift. Three consecutive perfusions (fifty minutes each) were performed in each rat, the drug being given in the second perfusion only. The rate of galactose disappearance was expressed as per cent of that in the first perfusion in the same rat.
Tolbutamide (50 mg./l kg. weight), glycodiazine (50 mg./l kg. weight), glisoxepid (BAY 4231, 2 mg./l kg. weight) and glibenclamide (0.25 mg./l kg. weight) were found to increase the rate of galactose disappearance in the second perfusion by 21 per cent, 5 per cent, 12 per cent and 25 per cent, respectively, and in the third perfusion by 21 per cent, 26 per cent, 32 per cent and 21 per cent, respectively, as compared to the rate in the corresponding perfusion of a control group. This increase was significant (P values < 0.05) with all drugs in the second and third perfusions with the exception of glisoxepid in the second perfusion. These results are discussed in relation to the action of insulin and the effect of diabetes on intestinal absorption of sugars.
Collapse
|
34
|
|