βγ subunits mediate the NPY enhancement of ATP-stimulated inositol phosphate formation

Neuropeptide Y (NPY) enhances ATP-stimulated inositol phosphate (InsP) formation in bovine chromaffin cells through an unknown mechanism. Chromaffin cells were transduced with the carboxyl terminus of β-adrenergic receptor kinase 1 (βARK1CT), a Gβγ subunits scavenger, using a recombinant adenovirus system. The adenovirus also expresses a green fluorescent protein (GFP) which serves as an index of transduction. Flow cytometry showed that up to 80% of chromaffin cells were transduced by the virus. There was a direct correlation between the βARK1CT inhibition of the NPY enhancement of ATP-stimulated InsP formation and the percent of cells expressing GFP (<F>r2=0.9993</F>). These results demonstrate that Gβγ subunits are required for the NPY enhancement of ATP-stimulated InsP formation in bovine chromaffin cells. [Copyright &y& Elsevier]