抄録
INOUE, M., SATO, T. and YOSHINAGA, K. Effects of Carbohydrates on Insulin Release from the Isolated Islets. Tohoku J. exp. Med., 1986, 149 (2), 183-189-Effects of monosaccharides and disaccharides on insulin release from the isolated islets were studied. (1) Insulin release from the isolated islets was 26.2μU/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. (2) 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. (3) D-Galactose and D-fructose also decreased insulin release. However, they potentiated the insulin release when D-glucose was also present. (4) Cellobiose and lactose, which have a β (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 theβ (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.
