Chronic ethanol administration induces tolerance to its inhibitory effects on smooth muscle contractions in the rat vas deferens, acting both pre- and postsynaptically.
No direct clinical implications; leaves open translation of ethanol tolerance mechanisms from rat vas deferens to humans.
Contractions of the rat vas deferens elicited by the addition of noradrenaline (NA), K+-depolarizing solutions or by electrical stimulation were recorded before and after incubation with ethanol 181 mM. In tissues from untreated rats, the contractions were inhibited 40-50% by such exposure. Injection of ethanol (2 g kg-1) significantly attenuated ethanol's reduction of peak tension generated by the lowest concentration of NA (10(-4) mM). Chronic administration of ethanol, 18-14 g kg-1 daily for two weeks, resulted in significant tolerance to ethanol. Tissues of treated animals demonstrated ethanol-induced decreases of roughly one-half those of the maltose dextrin (isocaloric) and water (fluid control) groups. This tolerance persisted for at least 48 h after ethanol treatment had been terminated. Overall, the data suggest that ethanol acts both pre- and postsynaptically to produce acute inhibition of smooth muscle contractions or tolerance to these actions upon chronic exposure.
No takes yet. Share an insight, caveat, or question.
DeTurck et al. (1986) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: