OBJECTIVE	A double-blind , placebo-controlled parallel study was conducted on the effect of mibefradil , both an L - and T-type Ca2 + - channel blocker with a more selective blockade of T-type channels , administered once daily for 1 week to normal male subjects , on blood pressure , intracellular cationic concentrations , sodium-proton exchange rate and 3H-thymidine incorporation in peripheral blood mononuclear cells ( PBMC ) .\