Inhibition of Insulin Release by Scorpion Toxin in Rat Pancreatic Islets

摘要: Toxin purified from venom of the scorpion Leiurus quinquestriatus was used to release norepinephrine adrenergic nerve terminals in isolated pancreatic islets perifused vitro. Addition toxin (10 µg./ml) perifusion medium caused a sixfold increase presence or absence 3 × 10 -5 M phenoxybenzamine. During 20 minutes stimulation with toxin, released an average 15 pg. per islet, which represented cent normal content islets. Insulin secretory rates response either 1.0 3.0 mg./ml. glucose were inhibited similarly by toxin. phenoxybenzamine abolished inhibition insulin Phenoxybenzamine alone did not affect insulin. Neither enhanced nor decreased reversed 20-minute wash-out period after infusion These results indicate that sympathetic rat islet contain considerable amounts can be The endings inhibit through alpha-adrenergic action is blocked