The influence off an acyl-amino-alcyl-benzoic acid (HB 699) on biosynthesis and secretion of insulin in isolated rat islets of Langerhans.

HB 699 belongs to a new class of hypoglycaemic agents, the acyl-amino-alcyl-benzoic acids. Its influence on bion-synthesis and secretion of insulin was studied in collagenase-isolated rat islets. During incubations for 3 hours together with 3H-leucine at 1 and 2 mg/ml glucose, HB 699 (10 micrograms/ml) reduced biosynthesis of proinsulin and insulin (3H-leucine incorporation), whereas insulin release was stimulated. During an incubation period of 2 hours in the absence of glucose, insulin release was enhanced both by HB 699 (50 micrograms/ml) and glibenclamide (10 micrograms/ml). At 1 mg/ml glucose, no additive or potentiating effect of HB 699 to that of glibenclamide was found regarding insulin release. When calcium ions were omitted insulin output in the presence of HB 699 and glucose was reduced. In conclusion, HB 699, although not belonging to the class of sulfonylureas, behaves very similar to these drugs concerning its influence on insulin biosynthesis and secretion in vitro. It acts as an initiator of insulin release, involving probably similar mechanisms as sulfonylureas do.