Hepatic-portal and cardiac infusion of CCK-8 and glucagon induce different effects on feeding.
In order to compare effects of circulating CCK-8 and glucagon on food intake, rats were provided with a permanently implanted catheter in the right atrium. Another cannula was implanted into the hepatic-portal vein by a new technique. After a standard fasting period graded loads of CCK-8 and glucagon were infused via these catheters during refeeding. Intracardiac glucagon and CCK loads dose-dependently suppressed meal size. Intraportal infusion of glucagon caused similar suppression compared to intracardiac administration. This may indicate a minor role of the liver as a target for the suppression of feeding by glucagon. In contrast, intraportal infusion of CCK-8 did not reduce food intake. The results indicate that CCK-8 is removed or inactivated by the liver. It is suggested that CCK-8 acts locally on vagal nerve endings to exert its suppressive action on food intake.
Strubbe
J H
JH
Department of Animal Physiology, University of Groningen, Haren, The Netherlands.
Wolsink
J G
JG
Schutte
A M
AM
Balkan
B
B
Prins
A J
AJ
D000818:Animals; D004305:Dose-Response Relationship, Drug; D005247:Feeding Behavior / Q000187:drug effects*; D005934:Glucagon / Q000008:administration & dosage*; D006325:Heart Atria; D008297:Male; D011169:Portal Vein; D051381:Rats; D011919:Rats, Inbred Strains; D012527:Satiation / Q000187:drug effects*; D012528:Satiety Response / Q000187:drug effects*; D012844:Sincalide / Q000008:administration & dosage*
D005934:Glucagon; D012844:Sincalide