Alcohol stimulates the expression of L-type voltage-operated Ca2+ channels in hepatic stellate cells.

Hepatic stellate cells (HSCs) have L-type voltage-operated Ca2+ channels (VOCC). However, the effect of ethanol on VOCC is unknown. To investigate the mechanism of ethanol-induced liver injury, the effect of ethanol on VOCC in HSCs was studied. In control cells, VOCC revealed by patch clamp techniques were not detected in cells cultured for less than 7 days; however, a faint VOCC mRNA by reverse-transcription polymerase chain reaction was recognized at the 5(th) day of culture. Detection of VOCC increased from 8% on day 7 to over 50% on day 14 in controls. With ethanol (100mM), it increased from 12% on day 5 to 100 % on day 14. Furthermore, expression of alpha-smooth muscle actin, shown as transformation to a myofibroblast, was recognized in ethanol-treated cells earlier and stronger than that in controls. VOCC were up-regulated by the treatment with ethanol associated with the induction of transformation to myofibroblasts.