| Abstract: | Two groups of receptors, one which develops a stimulating effect (alpha 1), the other an inhibitory effect hae recently been isolated in the alpha adrenergic group. In order to type the B cell adrenergic receptor of the endocrine pancreas, which mediates the inhibitory action exerted by the catecholamines on insulin secretion, the release of this hormone was evaluated in the presence of five alpha simpathomimetic substances that have a decreasing degree of efficiency on the adrenergic alpha 2 receptor of the presynaptic sympathic nerve terminal. The order of potency with which the alpha agonists tested depressed IRI secretion is superimposable on that of their potency on the sympathetic nerve and alpha 2 receptor. We concluded that adrenergic inhibition of insulin secretion is mediated by an alpha 2 receptor. |
