In Vivo Effect of 13 Leu Motilin on the Electric Activity of the Rabbit Sphincter of Oddi

Abstract

Myoelectrical activity of the sphincter of Oddi was studied in 15 anaesthetized and laparotomized male rabbits, before and after injection of various doses of 13 Leucine Motilin (13 L Motilin), a biological and structural analogue of natural motilin. It can be concluded that 13 L Motilin provoked an increase of the sphincter of Oddi spike activity with doses ranging from 0.1 to 1.6 x 10(-6) g/kg. This effect had begun one minute after the injection, reached its maximum at the second minute and lasted for fifteen minutes. The action of 13 L Motilin is dose-related between 0.2 and 0.6 x 10(-6).

Motility of the biliary system

“…Spontaneous phasic sphincter contractions are frequently absent in anesthetized primates but may be elicited by excitatory drugs. Cholecystokinin (CCK) inhibits sphincter of Oddi contractile activity in the human, dog, and cat (10,59) but stimulates contraction in the opossum and rabbit (8,158,159). Animals without a gallbladder have negligible sphincter of Oddi tone (110).…”

“…Subsequently CCK was shown to elicit sphincter of tractile activity in the rabbit, guinea pig, and opossum (8,158,159,204). Cholecystokinin also stimulates pancreatic enzyme secretion and enhances hepatic bile flow.…”