title: Effects of carbohydrates on insulin release from the isolated islets.
abstract: Effects of monosaccharides and disaccharides on insulin release from the isolated islets were studied. Insulin release from the isolated islets was 26.2 microU/5 islets/hr in carbohydrate-free medium and increased by the addition of D-glucose or D-mannose. L-Glucose was ineffective by itself but potentiated the insulin release stimulated by D-glucose. Effects of glucuronic acid and N-acetyl-D-glucosamine on insulin release were similar to those of L-glucose. Among monosaccharides, 2-deoxy-D-ribose, D-galactosamine, L-fucose, N-acetylneuraminic acid and D-ribose decreased insulin release and had no effect on insulin release by D-glucose. D-Galactose and D-fructose also decreased insulin release. However, they potentiated the insulin release when D-glucose was also present. Cellobiose and lactose, which have a beta(1-4) linkage to glucose molecule at the reducing end, inhibited insulin release stimulated by D-glucose. On the other hand, sucrose and maltose lacking the beta(1-4) linkage, did not inhibit the insulin release stimulated by D-glucose. These results suggest that insulin release from the isolated islets is stimulated by carbohydrates which can be metabolized in B-cells. Non-metabolizable analogues of D-glucose or disaccharides show different effects on glucose transport or glucose metabolism in the B-cells according to their chemical structures.
mesh_terms: D000818:Animals; D002241:Carbohydrates / Q000494:pharmacology*; D002475:Cellobiose / Q000494:pharmacology; D002478:Cells, Cultured; D004187:Disaccharides / Q000494:pharmacology; D005947:Glucose / Q000494:pharmacology; D007328:Insulin / Q000378:metabolism*; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism*; D008297:Male; D008320:Maltose / Q000494:pharmacology; D009005:Monosaccharides / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013329:Structure-Activity Relationship
chemical_list: D002241:Carbohydrates; D004187:Disaccharides; D007328:Insulin; D009005:Monosaccharides; D002475:Cellobiose; D008320:Maltose; D005947:Glucose