@article {Zheng1027, author = {Jialin Zheng and Peijin Zhang and Terry D. Hexum}, title = {Neuropeptide Y Inhibits Chromaffin Cell Nicotinic Receptor-Stimulated Tyrosine Hydroxylase Activity through a Receptor-Linked G Protein-Mediated Process}, volume = {52}, number = {6}, pages = {1027--1033}, year = {1997}, doi = {10.1124/mol.52.6.1027}, publisher = {American Society for Pharmacology and Experimental Therapeutics}, abstract = {Acetylcholine stimulation of bovine chromaffin cells results in increased norepinephrine and epinephrine secretion accompanied by a corresponding increase in synthesis. The addition of neuropeptide Y (NPY) to the culture medium prevents the increase in catecholamine synthesis but not secretion. Treatment of chromaffin cells with nicotine produces a concentration-dependent increase in tyrosine hydroxylase activity (IC50 = 1.2 μm) that is reduced if NPY is present during stimulation. Tyrosine hydroxylase activity decreases in a concentration-dependent fashion if increasing amounts of NPY are included in the culture medium, IC50 = 0.2 nm. Treatment with pertussis toxin completely prevents the effect of NPY. The rank order of potency for inhibition of tyrosine hydroxylase activity is NPY >= [Leu31,Pro34]NPY >= peptide YY \> NPY2{\textendash}36\>NPY13{\textendash}36 \> NPY18{\textendash}36 >= NPY26{\textendash}36 >> NPY1{\textendash}30, suggesting a NPY-Y1 receptor subtype. Examination of the effect of NPY on nicotine stimulation of chromaffin cell protein phosphorylation showed that NPY produces a concentration-dependent decrease in a 60-kDa protein, IC50 = 6.4 nm. The effect of NPY is pertussis toxin-sensitive. The rank order of potency is [Leu31,Pro34]NPY >= NPY >> NPY18{\textendash}36. Immunoprecipitation confirmed the identity of the 60-kDa protein as tyrosine hydroxylase.}, issn = {0026-895X}, URL = {https://molpharm.aspetjournals.org/content/52/6/1027}, eprint = {https://molpharm.aspetjournals.org/content/52/6/1027.full.pdf}, journal = {Molecular Pharmacology} }