Region-related Fos expression in hypothalamic dopaminergic neurons of rats by intraperitoneal administration of an endogenous satiety substance, 2-buten-4-olide.

An effect of 2-buten-4-olide (2-B4O), an endogenous satiety substance, on hypothalamic dopamine neurons of rats was studied by double-label immunohistochemistry for c-Fos and tyrosine hydroxylase (TH). Intraperitoneal administration of 2-B4O induced Fos-like immunoreactivity in TH-immunoreactive neurons in the periventricular area and paraventricular nucleus but not in the arcuate nucleus. Thus, the present results suggest that tuberohypophysial dopamine neurons are regulated under the influence of endogenous 2-B4O.