Actions of somatostatins on gastric smooth muscle cells - PubMed (original) (raw)
Actions of somatostatins on gastric smooth muscle cells
Z F Gu et al. Am J Physiol. 1992 Mar.
Abstract
The effects of somatostatin-28, somatostatin-14, and a synthetic somatostatin octapeptide analogue, D-Phe-Cys-Tyr-D-Trp-Lys-Thr-Cys-Nal-NH2 (cyclo SS-8) were examined on contraction of dispersed gastric smooth muscle cells from guinea pigs. The somatostatins did not cause contraction of gastric smooth muscle cells, nor did they inhibit carbachol-stimulated contraction. However, they reversed vasoactive intestinal peptide (VIP)-induced inhibition (relaxation) of carbachol-stimulated contraction. Somatostatin-28 had a half-maximal effect (EC50) at 1.6 +/- 0.8 nM, cyclo SS-8 at 0.6 +/- 0.3 nM, but somatostatin-14 had no effect even when used in concentrations as high as 1 microM. Incubation of muscle cells with peptidase inhibitors phosphoramidon (1 microM) plus amastatin (10 microM) had no effect on the EC50 of somatostatin-28 or cyclo SS-8 but increased the potency of somatostatin-14 greater than 1,000-fold. When peptides were incubated with muscle cells and the products applied to high-performance liquid chromatography, cyclo SS-8 was not degraded, but somatostatin-14 was rapidly degraded when present alone, and the addition of peptidase inhibitors partially inhibited the degradation. Cyclo SS-8 had its maximal effect at 0.5-1 min and inhibited relaxation induced by VIP, isoproterenol, glucagon, or dibutyryl adenosine 3',5'-cyclic monophosphate (DBcAMP). Cyclo SS-8 partially inhibited the increase in VIP-stimulated cAMP. Preincubation with pertussis toxin blocked the inhibitory action of cyclo SS-8 on VIP or DBcAMP-induced relaxation. These results indicate that gastric smooth muscle cells rapidly degrade somatostatin-14 and suggest that muscle cell peptidases could have a major effect on the actions of somatostatin-14.(ABSTRACT TRUNCATED AT 250 WORDS)
Similar articles
- Somatostatin receptor subtype 3 mediates the inhibitory action of somatostatin on gastric smooth muscle cells.
Gu ZF, Corleto VD, Mantey SA, Coy DH, Maton PN, Jensi RT. Gu ZF, et al. Am J Physiol. 1995 May;268(5 Pt 1):G739-48. doi: 10.1152/ajpgi.1995.268.5.G739. Am J Physiol. 1995. PMID: 7762657 - Galanin-induced relaxation in gastric smooth muscle cells is mediated by cyclic AMP.
Gu ZF, Pradhan TK, Coy DH, Jensen RT. Gu ZF, et al. Peptides. 1994;15(8):1425-30. doi: 10.1016/0196-9781(94)90119-8. Peptides. 1994. PMID: 7535425 - Inhibition of muscle cell relaxation by somatostatin: tissue-specific, cAMP-dependent, pertussis toxin-sensitive.
McHenry L, Murthy KS, Grider JR, Makhlouf GM. McHenry L, et al. Am J Physiol. 1991 Jul;261(1 Pt 1):G45-9. doi: 10.1152/ajpgi.1991.261.1.G45. Am J Physiol. 1991. PMID: 1677535 - Interaction of calcitonin gene-related peptides with pancreatic acinar cells and dispersed gastric smooth muscle cells.
Jensen RT, Zhou ZC, Gu ZF, Kitsukawa Y, Honda T, Maton PN. Jensen RT, et al. Ann N Y Acad Sci. 1992 Jun 30;657:268-88. doi: 10.1111/j.1749-6632.1992.tb22775.x. Ann N Y Acad Sci. 1992. PMID: 1379015 Review. No abstract available. - Pharmacodynamic effects of Sandostatin in the gastrointestinal tract.
Gyr KE, Meier R. Gyr KE, et al. Digestion. 1993;54 Suppl 1:14-9. doi: 10.1159/000201070. Digestion. 1993. PMID: 8103010 Review.
Cited by
- Regulatory mechanisms that modulate signalling by G-protein-coupled receptors.
Böhm SK, Grady EF, Bunnett NW. Böhm SK, et al. Biochem J. 1997 Feb 15;322 ( Pt 1)(Pt 1):1-18. doi: 10.1042/bj3220001. Biochem J. 1997. PMID: 9078236 Free PMC article. Review. - Characterization of somatostatin receptors in guinea-pig isolated ileum, vas deferens and right atrium.
Feniuk W, Dimech J, Humphrey PP. Feniuk W, et al. Br J Pharmacol. 1993 Nov;110(3):1156-64. doi: 10.1111/j.1476-5381.1993.tb13935.x. Br J Pharmacol. 1993. PMID: 7905341 Free PMC article. - VIP-induced relaxation of guinea-pig intestinal smooth muscle cells: sequential involvement of cyclic AMP and nitric oxide.
Rekik M, Delvaux M, Tack I, Frexinos J, Bueno L. Rekik M, et al. Br J Pharmacol. 1996 Jun;118(3):477-84. doi: 10.1111/j.1476-5381.1996.tb15428.x. Br J Pharmacol. 1996. PMID: 8762068 Free PMC article. - Mediation by SRIF1 receptors of the contractile action of somatostatin in rat isolated distal colon; studies using some novel SRIF analogues.
McKeen ES, Feniuk W, Humphrey PP. McKeen ES, et al. Br J Pharmacol. 1994 Oct;113(2):628-34. doi: 10.1111/j.1476-5381.1994.tb17036.x. Br J Pharmacol. 1994. PMID: 7834217 Free PMC article.
Publication types
MeSH terms
Substances
LinkOut - more resources
Full Text Sources