Ethanol and synaptosomal calcium homeostasis.
The effect of ethanol on synaptosomal calcium homeostasis was studied in the rat using the fluorescent dye, fura-2, and 45Ca uptake. The mitochondrial poison, cyanide, caused a substantial rise in intracellular free Ca2+ concentration, [Ca2+]i, over that of control synaptosomes. This rise was enhanced by ethanol. Ethanol also augmented the rise in [Ca2+]i induced by ouabain, indicating that modulation of Na(+)-Ca2+ exchange is probably not the underlying mechanism. The Ca2+ channel blockers, verapamil and La3+, also failed to inhibit the rise in [Ca2+]i caused by ethanol. Preincubation of synaptosomes with caffeine, however, caused a significant decrease in the rise of [Ca2+]i due to ethanol, suggesting that ethanol exerts effects on Ca2+ homeostasis at the level of the endoplasmic reticulum.
Davidson
M
M
Department of Biochemistry, University of Queensland, St Lucia, Australia.
Wilce
P
P
Shanley
B
B
D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002110:Caffeine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D004347:Drug Interactions; D000431:Ethanol / Q000494:pharmacology*; D006706:Homeostasis / Q000187:drug effects; D066298:In Vitro Techniques; D007811:Lanthanum / Q000494:pharmacology; D008297:Male; D010042:Ouabain / Q000494:pharmacology; D011190:Potassium Cyanide / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013574:Synaptosomes / Q000187:drug effects* / Q000378:metabolism; D014700:Verapamil / Q000494:pharmacology
D002110:Caffeine; D000431:Ethanol; D010042:Ouabain; D007811:Lanthanum; D014700:Verapamil; D011190:Potassium Cyanide; D002118:Calcium