A Sex-Specific Cytochrome P-450(F-1) Colocalized with Various Neuropeptides in the Paraventricular and Supraoptic Nuclei of Female Rats

Abstract

Numerous cells containing P-450(F-1) were detected in the magnocellular and parvocellular neurons of the paraventricular nucleus of the hypothalamus. Electron microscopic analysis of immunoreactive neurons has shown that P-450(F-1) immunoreactivity is present on the Golgi apparatus and rough endoplasmic reticulum. In the paraventricular nucleus, the P-450(F-1)-positive magnocellular neurons frequently contained oxytocin and some of them also contained CRF. Vasopressin was colocalized with P-450(F-1), but these neurons did not express CRF. In the supraoptic nucleus, P-450(F-1) was colocalized with oxytocin or CRF in single neurons, but not with vasopressin. No cells exhibiting the colocalization of both P-450(F-1) and somatostatin were observed in these nuclei. The results of the present study concerning colocalization of P-450 and peptides suggest that P-450(F-1) is involved in the hypothalamo-hypophyseal neuroendocrine function in the female rat.

Expression and distribution of CYP2C enzymes in rat basal ganglia

“…CYP2C11 can only be identified following ethanol treatment and microsequencing of the N-terminus . CYP2C12 has been detected in the preoptic area, supraoptic nucleus, hypothalamus, and paraventricular hypothalamic nucleus of female but not male rats (Hagihara et al, 1990;Lin et al, 1991). However, in these studies the antiserum raised against CYP2C12 also crossreacted strongly with CYP2C13, and weakly with CYP2C11 (Matsumoto et al, 1986).…”

“…P450 enzymes also exist in brain and CYP2C enzymes have been detected in the brains of rat (Hagihara et al, 1990;Lin et al, 1991;Watts et al, 1998;Zaphiropoulos and Wood, 1993), but relatively little is known about their distribution or regulation. CYP2C expression in rat brain may also be sexually dimorphic, based on immunohistochemical observations (Hagihara et al, 1990).…”