[Effect of ethanol on accumulation of Ca ions in intracellular structures of rat myometrium under conditions of first creating ethanol-dependent models].

In the experiments which have been conducted on digitonin-treated myometrium cell suspensions of nonpregnant rats the direct influence of ethanol in concentration 0-10% on the Ca2+ accumulation in mitochondria and endoplasmic reticulum have been studied. Studies have been conducted on the different models, such as, control (model I), subacute (model II), acute (model III) and chronic ethanol consumption (model IV). It has been shown for all models that the dependence of Ca2+ accumulation by mitochondria on the concentration of ethanol in incubation medium is bell-shaped. Acute and chronic ethanol consumption resulted in statistically reliable decrease in the amount of accumulated cations. Nevertheless the I50 values were the same for the models I-III and were 8-9%, although in the case of model IV this one was only 4.0 +/- 0.6%. The increase of ethanol concentration in the incubation medium caused of Ca2+ accumulation decreasing in the endoplasmic reticulum for all studied models, the values of I50 also decreased for models II-IV (2.8 +/- 0.2; 2.5 +/- 0.2 and 2.3 +/- 0.3% respectively) relative to the control (3.8 +/- 0.2%). At the level of model I oxytocin-inhibited component of the endoplasmic reticulum Ca2+ uptake was more stable to the ethanol effects than oxytocin-independent one. Although the sensitivity of the first one to the ethanol effects at the level of models II-IV rose, that parameter for the oxytocin-independent component was not changed. The mechanisms of ethanol effects on Ca2+ accumulation in the myometrium intracellular structures have been discussed.