Open AccessSuramin Inhibits Glucose-Induced Ca2+ Response in Single Rat Pancreatic .BETA. Cells.
Author(s) -
Hiroshi Kuromi,
Susumu Seino
Publication year - 1997
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - Uncategorized
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.73.179
Subject(s) - suramin , tolbutamide , purinergic receptor , medicine , endocrinology , secretagogue , calcium , chemistry , beta cell , insulin , biology , biochemistry , in vitro , adenosine , islet
It is reported that glucose releases ATP with insulin from pancreatic beta cells. Suramin (50-200 microM), a purinoceptor blocker, reversibly and dose-dependently inhibited the rise in cytoplasmic calcium concentration ([Ca2+]i) induced by glucose and by ATP in single beta cells. Suramin did not inhibit the glucose-induced increase in NAD(P)H fluorescence. The rise in [Ca2+]i induced by tolbutamide (an inhibitor of ATP-sensitive K+ channels), arginine (a cationic amino acid) and acetylcholine was unaffected by suramin (50-200 microM). This suggests that suramin inhibits the glucose-induced Ca2+ response without an inhibitory effect on glucose metabolism, K+ channels, voltage-dependent Ca2+ influx or Ca2+ release from internal Ca2+ stores and that a purinergic mechanism is involved in the glucose response in beta cells.