BETA-ADRENERGIC STIMULATION AND ISULIN RELEASE IN DOGS FOLLOWING HB-419

A new hypogylcaemic sulphonylurea HB 419 (Glybenzcyclamide) was injected intravenously into normal dogs (0.25 mg/kg). The drug produced within 30 min a fall in the concentration of plasma glucose and a rise in the concentration of immunoreactive insulin (IRI). When the alpha-adrenergic blocking agent phentolamine (5 mg per dog) was injected prior to the administration of HB 419, the rise in the concentration of plasma IRI was markedly potentiated. Insulin secretion was not appreciably stimulated by HB 419 when animals were treated with the beta-adrenergic blocking agent Kö 592, 1-(3-methylphenoxy)-3-isopropylaminopropanol-2-hydrochloride (0.1 mg/kg). The results of these experiments suggest that the mechanism of action of HB 419 on the pancreatic islets involves beta-adrenergic stimulation. © 1969 Springer-Verlag.