Bradykinin increases intracellular free Ca2+ concentration and promotes insulin secretion in the clonal beta-cell line, HIT-T15.
We have examined the effects of bradykinin (BK) on both the intracellular free calcium concentration ([Ca2+]i) and insulin secretion in the hamster beta-cell line, HIT-T15 cells. BK evoked a rise in [Ca2+]i in a dose-dependent manner. This response was suppressed by neomycin, suggesting that BK mobilizes Ca2+ from intracellular store via promotion of the phosphatidyl inositol turnover. Furthermore, BK also evoked insulin secretion. Both the BK-evoked rise in [Ca2+]i and insulin secretion were suppressed by the BK2 receptor antagonist, but not by the BK1 receptor antagonist. These results indicate that BK increases [Ca2+]i via BK2 receptor, thereby promoting insulin secretion in HIT-T15 cells.
Saito
Y
Y
Department of Laboratory Medicine, School of Medicine, Gunma University, Maebashi, Japan.
Kato
M
M
Kubohara
Y
Y
Kobayashi
I
I
Tatemoto
K
K
D000818:Animals; D001920:Bradykinin / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D006224:Cricetinae; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects* / Q000378:metabolism; D009355:Neomycin / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D007328:Insulin; D009355:Neomycin; D001920:Bradykinin; D002118:Calcium