Recently, we have shown that neuropeptide Y (NPY) is produced and upregulated in visceral adipose tissue of an early-life programmed rat model of central obesity. Moreover, we have demonstrated that NPY contributes to the pathogenesis of obesity. However, the role of NPY in regulating adipocyte metabolism is poorly understood. The present study examined the effects of NPY on adipocyte metabolism using 3T3-L1 adipocytes. We found that NPY potentiated isoproterenol (P-adrenergic agonist) stimulated lipolysis. This potentiation occurred upstream of adenylyl cyclase, since NPY did not enhance forskolin (direct activator of adenylyl cyclase) stimulated lipolysis. The potentiation was mediated by increased phosphorylation of hormone sensitive lipase. In contrast, NPY did not alter the expression of several key lipolytic and lipogenic enzymes/proteins or glucose uptake. Our results revealed a novel cross talk between the NPY and 3-adrenergic signaling pathways in regulating lipolysis and added a new dimension to the role NPY plays in regulating energy balanc
