RHEB and obesity due to melanocortin 4 receptor deficiency: In addition, interestingly, neuronal blockades, such as those achieved by bupranolol administration, hepatic vagotomy and pharmacological deafferentation, did not alter the serum TG levels in control mice, though TG elevations induced by hepatic Rheb expression or in obesity models were markedly inhibited by each form of neuronal blockade.