This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Copyright Permission Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Moro, F. Articles by Cuber, J. C. Search for Related Content PubMed PubMed Citation Articles by Moro, F. Articles by Cuber, J. C.

Release of Guanylin Immunoreactivity from the Isolated Vascularly Perfused Rat Colon¹

INSERM, U-45, Hôpital Edouard Herriot (F.M., E.N.-G., P.P., J.C.C.), 69437 Lyon; Laboratoire de Physiologie et Pharmacologie, Université de Savoie (S.P.), 73376 Le Bourget du Lac; and Unité d’Ecologie et de Physiologie du Système Digestif, Institut National de la Recherche Agronomique (F.L., P.P., J.C.C.), 78352 Jouy-en-Josas, France

Address all correspondence and requests for reprints to: Dr. Jean-Claude Cuber, INSERM, U-45, Hôpital Edouard-Herriot, Pavillon Hbis, 69437 Lyon Cedex 03, France. E-mail: cuber{at}lyon151.inserm.fr

The intestinal peptide guanylin regulates the electrolyte/water transport in the intestinal epithelium. The aim of the present study was to investigate the mechanisms that modulate its secretion in the isolated vascularly perfused rat colon by using a specific guanylin RIA. Intraarterial infusion of bethanechol (10^-4 M) or bombesin (10^-7 M) elicited a significant 6-fold increase in the release of guanylin immunoreactivity (G-IR) in the lumen. Bombesin-stimulated G-IR secretion was strongly reduced by tetrodotoxin, whereas atropine had no effect. VIP (10^-7 M) induced a moderate release of G-IR, whereas substance P, calcitonin gene-related peptide, peptide YY, somatostatin, and neurotensin were without effect. Dimethyl-PGE₂ (1.4 x 10^-5 M) or interleukin-1ß (2.5 x 10^-10 M) induced a 3-fold increase in G-IR in the lumen, whereas the degranulator compound bromolasalocid did not stimulate guanylin secretion. Forskolin (10^-5 M) or sodium nitroprusside (10^-4–10^-3 M) induced a significant release of G-IR. In contrast, PMA (10^-7 M) or ionophore A23187 (10^-6 M) did not modify basal secretion of G-IR. Upon stimulation of guanylin release with bombesin or bethanechol, an increase in G-IR in the portal effluent was also detected. The release of G-IR in the portal effluent was 40-fold lower than that of G-IR into the luminal perfusate. Additionally, analysis with gel chromatography revealed that the immunoreactive material released in the lumen or in the portal effluent coeluted with the 15-amino acid peptide originally isolated from rat intestine. In conclusion, the present data suggest that the enteric nervous system and immune cells may modulate guanylin release from the rat colon. The release of guanylin in the lumen and portal effluent suggests that this peptide may exert both luminal/paracrine and hormonal effects.

This article has been cited by other articles:

				N. G. Moss, D. A. Riguera, R. M. Solinga, M. M. Kessler, D. P. Zimmer, W. J. Arendshorst, M. G. Currie, and M. F. Goy The Natriuretic Peptide Uroguanylin Elicits Physiologic Actions Through 2 Distinct Topoisomers Hypertension, May 1, 2009; 53(5): 867 - 876. [Abstract] [Full Text] [PDF]

				J. A. Rudolph, J. A. Hawkins, and M. B. Cohen Proguanylin secretion and the role of negative-feedback inhibition in a villous epithelial cell line Am J Physiol Gastrointest Liver Physiol, September 1, 2002; 283(3): G695 - G702. [Abstract] [Full Text] [PDF]

				R. Potthast, E. Ehler, L. A. Scheving, A. Sindic, E. Schlatter, and M. Kuhn High Salt Intake Increases Uroguanylin Expression in Mouse Kidney Endocrinology, July 1, 2001; 142(7): 3087 - 3097. [Abstract] [Full Text] [PDF]