Increased content of neuropeptide Y in human pheochromocytoma cell cultures.

Cells from three human pheochromocytomas grown in monolayer culture for 21 days contained markedly greater amounts of neuropeptide Y (NPY) than freshly dissociated cells from the same tumors. The content of NPY did not consistently correlate with the extent of neurite outgrowth in the cultures and was not further increased in the presence of nerve growth factor. The content of NPY was decreased in the presence of 10(-5) M dexamethasone in two cultures. The findings suggest that human pheochromocytoma cultures may be useful in studies of cellular and molecular mechanisms regulating NPY production, and that these mechanisms may differ somewhat from those regulating production of other regulatory peptides in cultures of the same tumors.