Alpha-adrenergic influences on exocrine pancreatic secretion in the rabbit.
Action of phenylephrine (35 micrograms/Kg/min) alone or previously blocked by phentolamine (100 micrograms/Kg/min) on exocrine pancreatic secretion of anaesthetized rabbits has been studied, in basal state or under stimulation by secretin (1 C.U./Kg/h) or by the octapeptide of cholecystokinin (OP-CCK) (0.15 Ivy dog units/Kg/h). Phenylephrine increased arterial pressure. This effect was blocked by phentolamine. However no variations were seen in pancreatic blood flow in any of the experimental conditions assayed. Phenylephrine produced a secretin-like effect on hydroelectrolytic secretion in basal conditions. This action was maintained after the infusion of secretin but not after OP-CCK. This effect was not blocked by phentolamine. Phenylephrine increased protein secretion in the basal state, an action that was blocked by phentolamine. After secretin or OP-CCK stimulation phenylephrine did not increase protein secretion. It is concluded that phentolamine blocks the effects of phenylephrine on acinar cells but not on ductular cells.
Calvo
J J
JJ
Department of Physiology and Pharmacology, Faculty of Biology, University of Salamanca, Spain.
de Dios
I
I
Plaza
M A
MA
San Román
J I
JI
López
M A
MA
D000818:Animals; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism*; D010646:Phentolamine / Q000494:pharmacology; D010656:Phenylephrine / Q000494:pharmacology; D011817:Rabbits; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D012633:Secretin / Q000494:pharmacology; D012844:Sincalide / Q000494:pharmacology
D011942:Receptors, Adrenergic, alpha; D012633:Secretin; D010656:Phenylephrine; D012844:Sincalide; D010646:Phentolamine