Jpn. J. Pharmacol. 86 (2), 244-247 (2001)

GTPgS-Induced Ca2+ Activated Cl Currents: Its Stable Induction by Gqa Overexpression in Xenopus Oocytes

Muneshige Kaibara*, Yoshihisa Nagase, Osamu Murasaki, Yasuhito Uezono, Yoshiyuki Doi and Kohtaro Taniyama

Department of Pharmacology, Nagasaki University School of Medicine, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan

*Corresponding author. FAX: +81-95-549-7048, E-mail:

Abstract: In native Xenopus oocytes, injection of guanosine 5'-O-(3-thiotriphosphate) (GTPgS) (30 mM, 5 nl) did not induce Cl current in 11 out of 22 oocytes. Injection of increased concentration of GTPgS (100 mM, 5 nl) into the oocytes induced Cl currents in 16 out of 17 oocytes; however, the size of the induced currents was extremely varied. In oocytes overexpressing Gqa, GTPgS (30 mM, 5 nl) faithfully evoked Ca2+-activated Cl currents. These results indicate that heterogeneous expression of Gqa in Xenopus oocytes provides a useful system for studying the functional roles of Gqa in regulating cellular events.

Keywords: Gq, GTPgS, Oocyte
[Back to TOC]