AJP - Gastrointestinal and Liver Physiology, Vol 270, Issue 3 492-G497, Copyright © 1996 by American Physiological Society

ARTICLES

Evidence for VIP-induced increase in NO production in myenteric neurons of opossum internal anal sphincter

S. Chakder and S. Rattan
Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA.

A significant interaction between vasoactive intestinal polypeptide (VIP) and nitric oxide (NO) has been reported in neurotransmission of the gastrointestinal tract, including the internal anal sphincter (IAS). The exact site of this NO release from the IAS in response to VIP is not known. Studies were carried out to determine the site of this VIP-induced NO release in opossum IAS. NO synthase (NOS) activity was quantitated by determining L--3H-citrulline production from L[3H]arginine in isolated myenteric ganglia and smooth muscle cells of the IAS. L-[3H]citrulline production was determined before and after treatment with either the ganglionic stimulant 1,1-dimethyl-4-phenylpiperazinium iodide (DMPP), VIP, or peptide histidine isoleucine (PHI) in the absence and presence of the neurotoxin tetrodotoxin and the NOS inhibitor NG-nitro-L-arginine (L-NNA). Smooth muscle cells and ganglia were preloaded with L-[3H]arginine for 5 min and treated with VIP for 1 and 5 min. DMPP and VIP caused a significant increase in L-[3H]citrulline formation in myenteric ganglia at both time periods, whereas in smooth muscle cells there was a moderate but significant increase in L-[3H]citrulline production only at 5 min of VIP treatment. VIP-induced relaxation of isolated smooth muscle cells of the IAS was not affected by L-NNA. The increase in NOS activity of myenteric ganglia by DMPP and VIP was sensitive to neurotoxin and the NOS inhibitor. The data suggest that the increase in NO production in response to VIP in the IAS occurs mainly from the myenteric neurons, with some contribution from the smooth muscle cells.

This article has been cited by other articles:

				A. Terauchi, D. Kobayashi, and H. Mashimo Distinct roles of nitric oxide synthases and interstitial cells of Cajal in rectoanal relaxation Am J Physiol Gastrointest Liver Physiol, August 1, 2005; 289(2): G291 - G299. [Abstract] [Full Text] [PDF]

				F. Mule, M. G. Vannucchi, L. Corsani, R. Serio, and M. S. Faussone-Pellegrini Myogenic NOS and endogenous NO production are defective in colon from dystrophic (mdx) mice Am J Physiol Gastrointest Liver Physiol, November 1, 2001; 281(5): G1264 - G1270. [Abstract] [Full Text] [PDF]

				S. Chakder, D. N. K. Sarma, and S. Rattan Mechanism of internal anal sphincter smooth muscle relaxation by phorbol 12,13-dibutyrate Am J Physiol Gastrointest Liver Physiol, June 1, 2001; 280(6): G1341 - G1350. [Abstract] [Full Text] [PDF]

				R. Battish, G.-Y. Cao, R. B. Lynn, S. Chakder, and S. Rattan Heme oxygenase-2 distribution in anorectum: colocalization with neuronal nitric oxide synthase Am J Physiol Gastrointest Liver Physiol, January 1, 2000; 278(1): G148 - G155. [Abstract] [Full Text] [PDF]

				T Wester, D S O'Briain, and P Puri Notable postnatal alterations in the myenteric plexus of normal human bowel Gut, May 1, 1999; 44(5): 666 - 674. [Abstract] [Full Text] [PDF]

				S. Chakder and S. Rattan Mechanisms and Sites of Action of Endothelins 1 and 2 on the Opossum Internal Anal Sphincter Smooth Muscle Tone In Vitro J. Pharmacol. Exp. Ther., January 1, 1999; 288(1): 239 - 246. [Abstract] [Full Text]

				B.-Q. Teng, K. S. Murthy, J. F. Kuemmerle, J. R. Grider, K. Sase, T. Michel, and G. M. Makhlouf Expression of endothelial nitric oxide synthase in human and rabbit gastrointestinal smooth muscle cells Am J Physiol Gastrointest Liver Physiol, August 1, 1998; 275(2): G342 - G351. [Abstract] [Full Text] [PDF]

				H. KURIYAMA, K. KITAMURA, T. ITOH, and R. INOUE Physiological Features of Visceral Smooth Muscle Cells, With Special Reference to Receptors and Ion Channels Physiol Rev, July 1, 1998; 78(3): 811 - 920. [Abstract] [Full Text] [PDF]

				S. Chakder, A. Bandyopadhyay, and S. Rattan Neuronal NOS gene expression in gastrointestinal myenteric neurons and smooth muscle cells Am J Physiol Cell Physiol, December 1, 1997; 273(6): C1868 - C1875. [Abstract] [Full Text] [PDF]

				E. Ekblad and F. Sundler Motor Responses in Rat Ileum Evoked by Nitric Oxide Donors vs. Field Stimulation: Modulation by Pituitary Adenylate Cyclase-Activating Peptide, Forskolin and Guanylate Cyclase Inhibitors J. Pharmacol. Exp. Ther., October 1, 1997; 283(1): 23 - 28. [Abstract] [Full Text]