Effects of epinephrine on plasma cholesterol levels in rats

The present study was undertaken to evaluate whether epinephrine increases plasma cholesterol in rats. Epinephrine suspended in sesame oil was subcutaneously administered at 21:00 hr (9 PM). Blood was drawn 12 hr later, and plasma cholesterol was shown to be increased by epinephrine in a dose-dependent manner (0.5-2.0 mg/kg). This epinephrine-induced hypercholesterolemia was enhanced by phentolamine (25 mg/kg) and inhibited by propranolol (25 mg/kg). Although the effect of epinephrine in normal rats was abolished by adrenalectomy, corticosterone (10 mg/kg) increased plasma cholesterol in both normal and adrenalectomized rats. These results demonstrate that epinephrine increases plasma cholesterol levels in rats, and that the effect of epinephrine appears to be mediated by the beta-adrenergic receptors, depending upon adequate amounts of corticosteroids.