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 increased lipogenesis and inhibition of catecholamine-induced lipolysis, in rat adipocytes that have not been exposed to GH during the preceding three hours. We found that OPC3911, a highly specific inhibitor of the cGMP-inhibited cAMP phosphodiesterase, completely blocked the antilipolytic but not the lipogenic effect of GH. This indicates that the antilipolytic effect of GH is mediated through activation of this phosphodiesterase leading to reduction of cAMP levels in the same manner as has been shown for insulin.