Stimulation of insulin release by thiols.
The effects of thiol compounds on insulin release were studied in microdissected pancreatic islets of non-inbred ob/ob micemin control experiments the reactivity of thiols against 6,6'-dithiodinicotinic acid and the degradation of mouse insulin were measured. At a concentration of 0.1 mM, 1-thio-D-glucose or reduced glutathione potentiated the insulin-releasing action of 10 mM D-glucose without affecting glucose oxidation. When tested at a concentration equivalent to about 0.1 mM reactive thiol, dextran-linked L-cysteine also potentiated the glucose-induced insulin secretion. In microperifusion experiments the insulin-releasing action of 1-thio-D-glucose was found to exhibit a rapid onset followed by a decline of the secretory rate to values lower than those observed with 10 mMD-glucose alone. No thiol stimulated insulin release in the absence of glucose. It is suggested that thiol compounds stimulate insulin release by splitting membrane disulphides in the beta-cells.
D000818:Animals; D003545:Cysteine / Q000494:pharmacology; D003911:Dextrans; D005947:Glucose / Q000378:metabolism; D005978:Glutathione / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008820:Mice, Obese; D010477:Perfusion; D013438:Sulfhydryl Compounds / Q000494:pharmacology*; D013997:Time Factors
D003911:Dextrans; D007328:Insulin; D013438:Sulfhydryl Compounds; D005978:Glutathione; D005947:Glucose; D003545:Cysteine