AJP - Gastrointestinal and Liver Physiology, Vol 240, Issue 3 217-G220, Copyright © 1981 by American Physiological Society
Inhibition of canine interdigestive proximal gastric motility by cholecystokinin octapeptide
J. C. Schang and K. A. Kelly
Feeding abolishes cyclic interdigestive motility and decreases intraluminal
pressure in autotransplanted pouches of canine proximal stomach. Our aim
was to determine whether cholecystokinin might be the hormonal messenger
involved. In four conscious dogs with autotransplanted proximal gastric
pouches and chronic duodenal electrodes, intrapouch pressure and duodenal
myoelectric activity were measured during fasting, while cholecystokinin
octapeptide (CCK-OP) was infused intravenously for 4 h at doses 0, 15, 31,
62, 125, and 250 mg . kg-1 . h-1. Each dose was given five times to each
animal. Cholecystokinin octapeptide inhibited the interdigestive cycles in
both pouch and duodenum and decreased the pressure in the pouch. The
threshold for these effects was 31 ng . kg-1 . h-1, and the ED50 was 62 ng
. kg-1 . h-1. The dose of 125 ng . kg-1 . h-1 suppressed the cycles nearly
completely and decreased mean +/- SE intrapouch pressure from 15.3 +/- 1.1
to 6.3 +/- 2.8 cmH2O . min (P less than 0.001). After the infusions were
stopped, cyclic activity and intrapouch pressure returned promptly to
control values. We concluded that CCK-OP at "physiological" doses abolished
interdigestive cycles and decreased intraluminal pressure in
autotransplanted pouches of canine proximal stomach.
