Neuropeptide Y secretion from bovine chromaffin cells inhibits cyclic AMP accumulation

Neuropeptide Y (NPY) is secreted from bovine chromaffin cells in response to nicotinic receptor stimulation and may exhibit autocrine, paracrine or endocrine effects. Stimulation of bovine chromaffin cells with nicotine followed by the addition of forskolin (FSK) to the media results in a decrease in cyclic AMP accumulation compared to that seen in the absence of nicotine. Pertussis toxin (PTX) treatment or the addition of BIBP 3226, a selective NPY Y1 receptor antagonist prevents the inhibitory effect of nicotine. Fractionation of media obtained from cells stimulated with nicotine reveals an NPY-like substance that inhibits FSK-stimulated cAMP accumulation. Thus, an NPY-like substance can be secreted from bovine chromaffin cells in quantities sufficient to inhibit FSK-stimulated cAMP accumulation. These results suggest that NPY can act in an autocrine fashion to regulate chromaffin cell function.