Effect of lovastatin on the interaction between high density lipoprotein and cultured rat adrenocortical cells

Preincubation of rat adrenocortical cells with lovastatin inhibits high density lipoprotein (HDL3) interaction with rat adrenocortical cells in a dose- and time-dependent fashion. Lovastatin causes a decrease in the number of binding sites and a moderate increase in the affinity of HDL binding to cells. Lovastatin also produced a dose- and time-dependent inhibition of cholesterol synthesis in these cells. Dose-dependence, but not time-dependence, of the inhibition of cholesterol synthesis, correlates with that of HDL binding (r = 0.91, P less than 0.004). Incubation of cells with lovastatin for up to 24 h does not change their free or total cholesterol content. The inhibitory effect was apparently not due to a modification of HDL by lovastatin. These results indicate that lovastatin causes a down-regulation of HDL binding sites on cultured rat adrenocortical cells.