Expression of neuropeptide Y and pro-opiomelanocortin in hypothalamic arcuate nucleus in 17α-ethinyl estradiol-induced intrahepatic cholestasis pregnant rat offspring

Abstract

The purpose of this study was to investigate the expression of neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) in the hypothalamic arcuate nucleus of intrahepatic cholestasis pregnant (ICP) offspring. The model of ICP rats was established by injecting s.c. 17α-ethinyl estradiol. The expression of NPY and POMC in female offspring was determined by quantitative real-time reverse transcription polymerase chain reaction, western blotting and immunohistochemistry at birthday and 6 months. ICP group offspring had lower bodyweight at birthday. ICP offspring were markedly heavier than control offspring after 6 months. mRNA and protein expression of NPY and POMC significantly increased at 6 months as compared with the birthday among control offspring. Among ICP offspring, mRNA and protein expression of NPY and POMC also were higher at 6 months than at birthday. The mRNA and protein expression of NPY were higher in ICP offspring than that of control offspring at birthday. The mRNA and protein expression of POMC were decreased in ICP offspring than that of control offspring. After 6 months, the mRNA expression and protein expression of NPY also were higher in ICP offspring than that of control offspring. The mRNA expression and protein expression of POMC also were decreased in ICP offspring than that of control offspring. The results were confirmed by immunohistochemistry. ICP offspring demonstrated evidence of persistent appetite stimulation with significantly upregulated NPY expression and reduced POMC expression at birthday and 6 months. ICP offspring showed a hunger state and then gained weight.