![]() |
|
|
D Mullikin-Kilpatrick, ND Mehta, JD Hildebrandt and SN Treistman
Department of Pharmacology, University of Massachusetts Medical Center, Worcester 01655, USA.
The effects of acute exposure to 25 mM ethanol on high voltage- activated, L-type Ca2+ channels in undifferentiated and nerve growth factor-treated pheochromocytoma (PC-12) cells were examined using conventional, whole-cell, patch-clamp techniques. Acute exposure to 25 mM ethanol inhibited macroscopic L-type Ca2+ currents in undifferentiated PC-12 cells significantly more than in nerve growth factor-treated PC-12 cells. Intracellular infusion with guanosine-5'-O- (2-thio)diphosphate or pretreatment with pertussis toxin reduced ethanol inhibition in undifferentiated cells without altering inhibition in nerve growth factor-treated cells, suggesting the involvement of a G protein in ethanol inhibition of Ca2+ channels in undifferentiated cells. Intracellular infusion with an affinity- purified antibody that recognizes the carboxyl termini of alpha i1 and alpha i2 significantly reduced ethanol inhibition in undifferentiated cells, in contrast to the effects of antibodies that recognize the carboxyl termini of alpha oA and alpha oB. None of these antibodies reduced ethanol inhibition in nerve growth factor-treated cells. These results indicate that Gi1 alpha or Gi2 alpha mediates ethanol inhibition of L-type Ca2+ channel currents in undifferentiated but not in nerve growth factor-treated PC-12 cells.
This article has been cited by other articles:
![]() |
C. A. Wells, J. Dingus, and J. D. Hildebrandt Role of the Chaperonin CCT/TRiC Complex in G Protein beta{gamma}-Dimer Assembly J. Biol. Chem., July 21, 2006; 281(29): 20221 - 20232. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. McMahon, R. Andersen, P. Metten, J. C. Crabbe, and R. O. Messing Protein Kinase C epsilon Mediates Up-Regulation of N-Type Calcium Channels by Ethanol Mol. Pharmacol., January 1, 2000; 57(1): 53 - 58. [Abstract] [Full Text] |
||||
![]() |
E. H. Gerstin Jr., T. McMahon, J. Dadgar, and R. O. Messing Protein Kinase Cdelta Mediates Ethanol-induced Up-regulation of L-type Calcium Channels J. Biol. Chem., June 26, 1998; 273(26): 16409 - 16414. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. M. Dopico, V. Anantharam, and S. N. Treistman Ethanol Increases the Activity of Ca++-Dependent K+ (mslo) Channels: Functional Interaction with Cytosolic Ca++ J. Pharmacol. Exp. Ther., January 1, 1998; 284(1): 258 - 268. [Abstract] [Full Text] |
||||