An alpha 1-adrenoceptor-sensitive mechanism is responsible for the adrenergic inhibition of insulin secretion in the pig pancreas.
The alpha-adrenoceptor subtype mediating inhibition of insulin secretion in the pig was examined in an isolated pancreas preparation perfused with 5 mM glucose. It was found that noradrenaline and the alpha 1-adrenoceptor agonist phenylephrine, but not the alpha 2-adrenoceptor agonist UK 14,304, inhibited insulin secretion. The effect of noradrenaline was abolished by the alpha 1-adrenoceptor antagonist prazosin but was not affected by the alpha 2-adrenoceptor antagonist idazoxan. The inhibitory effect of phenylephrine was also inhibited by prazosin. Thus, in the pig, the alpha-adrenoceptor subtype inhibiting insulin secretion is of the alpha 1-type, which is different from the subtype involved in other species.
Gregersen
H
H
Department of Surgery L, Aarhus Kommunehospital, Aarhus University Hospital, Denmark.
Jensen
S L
SL
Ahrén
B
B
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D004386:Duodenum / Q000502:physiology; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D009638:Norepinephrine / Q000494:pharmacology; D010477:Perfusion; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000502:physiology*; D013552:Swine
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D007328:Insulin; D011942:Receptors, Adrenergic, alpha; D009638:Norepinephrine