Issue Archive

MA Yong-Jie

2College of Information Engineering, Taishan Medical University, Taian 271016, China

Abstract

Whole cell patch-clamp recorrding techniques were used to compare the electrophysiological properties between deayed rectifier K+ current of rabbit vascular smooth muscle cell(VSMC)and the cloned Kvl.5 channel.When VSMC is clamped at -40 mV,depolarizing the membrane potential at increasing steps of 10 mV could evoke a series of outward potassium cmrrents without any deactivation.The V1/2 of the activation curve was 27.2 mV.The curmnts decrease obviously after adding 100 mmol/L TEA or 1 mmol/L 4AP in the perfusate.When the concentration of extracellular Ca2+ was decreased from 1.5 mmol/L to 0.5 or 0 mmol/L,the currents did not show much change,while in HBK7(cloned Kv1.5 channel cell)held at-8O mV,similar steparise depolarizaton could also produce a series of outward potassium currents without any deactivation decayed.V1/2 of the activation was 0.8 mV.4AP inhibited the cloned channel current with IC50 of 7.3 mmol/L,showing neither frequency-or use-dependence.

Key words: ;;;;;

Received: 　　Accepted:

Corresponding author: 　　E-mail:

Citing This Article：

MA Yong-Jie. . Acta Physiol Sin 1998; 50 (1): (in Chinese with English abstract).