Single‐channel Ba2+ currents in insulin‐secreting cells are activated by glyceraldehyde stimulation

FEBS Letters

Petersen, O.H.¹  Petersen, J.U.H.¹  Velasco, J.M.¹ 

[1] MRC Secretory Control Research Group, The Physiological Laboratory, University of Liverpool, PO Box 147, Brownlow Hill, Liverpool L69 3 BX, England

关键词: Patch-clamp;    Ca2+ channel;    Ba2+ current;    Glyceraldehyde;    (RINm5F cell);   

DOI  :  10.1016/0014-5793(88)80851-2

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Single-channel Ba²⁺ current recordings have been made from the insulin-secreting cell line RINm5F with the patch-clamp technique. Depolarization evokes opening of Ca²⁺ (Ba²⁺) channels with a relatively high conductance (30 pS) and during the 200 ms depolarizing pulses there is no inactivation. The threshold is high as 50 mV depolarization from the resting membrane potential of −70 mV is required for any channel opening to occur. Glyceraldehyde, a substance evoking insulin secretion from the RINm5F cells, enhances the voltage-activated Ca²⁺ channel opening by increasing the mean open time and decreasing the longer of the two mean shut times and also decreases the voltage threshold for channel opening.

【 授权许可】

Unknown