Elevated neuropeptide Y gene expression and release during hypoglycemic stress.

Our previous studies show that neuropeptide Y (NPY) is involved in mediating sympathetic nerve stimulation-induced vasoconstriction. Insulin hypoglycemia is known to produce increased sympathetic output and elevated arterial pressure. The present study examined the role of NPY in the hypertensive response to insulin by examining the effects of insulin on NPY gene expression, tissue content and release. Subcutaneous injection of insulin produced an immediate increase in plasma NPY immunoreactivity (NPYir) and delayed increases in adrenal and neuronal NPY mRNA and adrenal NPYir in rats. These results suggest that NPY may play a role in insulin-induced hypertension.