J Physiol Wellcome Trust-funded researchers
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
 QUICK SEARCH:   [advanced]


     


J Physiol Vol 302 pp 549-557
Copyright © 1980 by The Physiological Society
This Article
Right arrow Full Text (PDF)
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Eklund, S.
Right arrow Articles by Sjöqvist, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Eklund, S.
Right arrow Articles by Sjöqvist, A.

Vasoactive intestinal polypeptide, 5-hydroxytryptamine and reflex hyperaemia in the small intestine of the cat

S. Eklund*, J. Fahrenkrug, M. Jodal*, O. Lundgren*, O. B. Schaffalitzky de Muckadell and A. Sjöqvist*

Department of Clinical Chemistry, Bispebjerg Hospital, Copenhagen, Denmark

Department of Physiology, University of Göteborg, Sweden

1. The release of vasoactive intestinal polypeptide (VIP) into venous blood from the small intestine of the cat was studied when mechanically stimulating the intestinal mucosa and during close intra-arterial infusions of 5-hydroxytryptamine (5-HT) or isopropylnoradrenaline. The studies were performed on anaesthetized cats given atropine.

2. Mechanical stimulation of the intestinal mucosa induced a vasodilatation and a release of VIP into the intestinal venous blood. Intra-arterial administration of tetrodotoxin was given in doses that blocked the vasoconstrictor effect of the regional sympathetic nerve fibres. This also abolished the vascular response and the release of VIP into blood upon mechanical stimulation.

3. Close intra-arterial administration of 2-bromo-lysergic acid diethylamide reduced the VIP release and the intestinal vasodilatation upon mucosal stimulation to largely the same extent.

4. Close intra-arterial infusions of 5-HT produced a marked release of VIP from the intestine and a moderate vasodilatation. Close intra-arterial infusions of isopropylnoradrenaline, which caused a pronounced intestinal vasodilatation, evoked only a small release of VIP.

5. The results are compatible with the hypothesis that the vasodilatation in the gut, induced by mechanical mucosal stimulation, is mediated via an intramural nervous reflex containing a neurone capable of releasing VIP. It is proposed that the nervous reflex is activated by the release of 5-HT from the enterochromaffin cells evoked by mechanical stimulation of the mucosa.







HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1980 The Physiological Society.