SPECIFIC-INHIBITION OF THE CGMP-INHIBITED CAMP-PHOSPHODIESTERASE BLOCKS THE INSULIN-LIKE ANTILIPOLYTIC EFFECT OF GROWTH-HORMONE IN RAT ADIPOCYTES

Growth hormone (GH) exerts acute insulin-like effects, such as increas ed lipogenesis and inhibition of catecholamine-induced lipolysis, in r at adipocytes that have not been exposed to GH during the preceding th ree hours. We found that OPC3911, a highly specific inhibitor of the c GMP-inhibited cAMP phosphodiesterase, completely blocked the antilipol ytic but not the lipogenic effect of GH. This indicates that the antil ipolytic effect of GH is mediated through activation of this phosphodi esterase leading to reduction of cAMP levels in the same manner as has been shown for insulin.