Reserpine induces increase in neuropeptide Y immunoreactivity in rat amygdala neurons.

The effect of reserpine, a monoamine-depleting agent, on the neuropeptide Y (NPY) immunoreactivity was studied immunohistochemically in the amygdaloid complex (amygdala) of rat brain. It was found that reserpine, at a dose of 10 mg/kg i.p., after 24 h, enhanced the NPY immunoreactivity in amygdala neurons, which was expressed as an increase in the staining intensity and in the number of immunoreactive neurons visible in that structure. The obtained results suggest that monoamines take part in the regulation of NPY expression in amygdala neurons of rat brain, and that elimination of these monoaminergic regulation leads to an increase in the NPY content in that structure.