Secondary Logo

Journal Logo

Institutional members access full text with Ovid®

A calcium channel reversibly blocked by ω-conotoxin GVIA lacking the class D α1 subunit

Mermelstein, Paul G.1; Surmeier, D James1,2

Membrane and Cellular Biophysics and Biochemistry

IN acutely dissociated rat medium-spiny neostriatal neurons, a substantial fraction (∼40%) of the calcium current block by ω-conotoxin-GVIA (CgTx) reverses rapidly with washing. The reversibly blocked current differed in voltage dependence from the current irreversibly blocked by CgTx. To test the hypothesis that the reversibly blocked current was attributable to calcium channels with a class D α1 subunit, acutely isolated neurons were subjected to combined patch clamp/reverse transcription-polymerase chain reaction analysis. These studies revealed no correlation between the reversibility of the CgTx block and the expression of class D α1 subunit mRNA.

1Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee, 855 Monroe Ave, Memphis, TN 38163, USA

2Corresponding Author: D. James Surmeier.

ACKNOWLEDGEMENTS: We would like to thank Dr Wen-Jie Song, Zhen Yan and Dr Lorina Dudkin for their technical assistance. This work was supported by USPHS grants NS-34696 and NS-26473 to D.J.S. and NS-10028 to P.G.M.

Received 7 October 1996; accepted 25 October 1996

© Lippincott-Raven Publishers.