[The effect of dibutyryl cAMP, verapamil and adrenaline on cholesterol mobilization from macrophages]

The capacity of dibutyryladenosine-3':5'-cyclic phosphate (dibutyryl cAMP), verapamil and epinephrine to modulate cholesterol (CH) excretion was studied in the stored (4-14C)-CH rat macrophages. The experiments indicated that in the absence of high density lipoproteins (HDL) the addition of dibutyryl cAMP (0.2 mmol), verapamil (0.05 mmol), epinephrine (0.05 mmol) in cultured medium did not influence the excretion of the stored (4-14C)-CH from macrophages during 4, 8 and 18 hours. The addition of the drugs in the presence of HDL resulted in an increase in the excretion of (4-14C)-CH from macrophages during incubation. The data indicate that the drugs which increase the cellular concentration of cAMP can induce the mobilization of CH from macrophages in the presence of acceptors of CH.