Vasoactive intestinal peptide modulates t lymphocyte migration in peyer's patches of rat small intestine. Miura, Soichiro, Hiroshi Serizawa, Yoshikazu Tsuzuki, Iwao Kurose, Makoto Suematsu, Hajime Higuchi, Takeharu Shigematsu, Ryota Hokari, Masahiko Hirokawa, Hiroyuki Kimura, and Hiromasa Ishii. Departments of Internal Medicine and Biochemistry, School of Medicine, Keio University, 35 Shinanomachi, Shinjuku-ku, Tokyo 160, Japan
APStracts 3:0155G, 1996.
Although vasoactive intestinal peptide has been postulated to function in modulation of T-cell trafficking, the exact mechanism has not been elucidated in vivo. In the present study, the effects of vasoactive intestinal peptide on T-lymphocyte migration were examined in rat Peyer's patches. T-lymphocytes collected from intestinal lymph of rats were labeled with carboxyfluorescein diacetate succinimidyl ester, and injected into the jugular vein. Peyer's patches of the recipient rats were observed with intravital fluorescence microscopy. In vivo intraarterial infusion of or in vitro incubation with vasoactive intestinal peptide did not affect the initial lymphocyte interaction with postcapillary venules of Peyer's patches. However, these treatments with vasoactive intestinal peptide significantly inhibited transendothelial migration and also significantly blocked the interstitial migration of T-cells and inhibited their subsequent appearance in the interfollicular lymphatics. Treatment with cyclic AMP inducing agents resulted in similar inhibitory effects on T -lymphocyte migration in Peyer's patches. In conclusion, vasoactive intestinal peptide has significant inhibitory effects on T-lymphocyte migration in Peyer's patches, possibly mediated by the elevation of the intracellular cyclic AMP concentrations.

Received 25 January 1996; accepted in final form 26 July 1996. 
APS Manuscript Number G38-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 29 August 1996