These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Effects of C-terminal octapeptide of cholecystokinin and prostaglandins on adrenergic functions in the guinea-pig gallbladder and sphincter of Oddi.
    Author: Nakata K, Kurahashi K.
    Journal: Jpn J Pharmacol; 1981 Feb; 31(1):77-83. PubMed ID: 7253345.
    Abstract:
    Effects of C-terminal octapeptide of cholecystokinin (C8-CCK) and prostaglandins E1, E2 and E alpha on noradrenaline-induced responses and 3H-noradrenaline release in the gallbladder and sphincter of Oddi of guinea pigs were examined. In the sphincter of Oddi, noradrenaline in low concentrations induced a relaxation which was blocked by either phentolamine or propranolol, while noradrenaline in high concentrations induced a contraction which was blocked by phentolamine. These results suggest the existence of excitatory and inhibitory alpha-receptors and inhibitory beta-receptors in the sphincter of Oddi. In the gallbladder, the adrenergic receptors are alpha-excitatory and beta-inhibitory. C8-CCK (10(-9) g/ml) potentiated both contractile and relaxing responses to noradrenaline, in the gallbladder. The same concentration of prostaglandins potentiated only contractile response to noradrenaline. In the sphincter of Oddi, noradrenaline-induced responses were not affected by C8-CCK and prostaglandins. Prostaglandins inhibited 3H-efflux evoked by electrical stimulation, while C8-CCK had no effect on the 3H-efflux from both preparations. These results suggest that C8-CCK enhances the contractile and relaxing responses to noradrenaline, and that prostaglandins act in a similar way on the postsynaptic response and, in addition, inhibit presynaptically the release of noradrenaline in the gallbladder. In the sphincter of Oddi, only prostaglandins inhibit the presynaptic event.
    [Abstract] [Full Text] [Related] [New Search]