Proteomic Changes In The Hypothalamus Of Female Rats Injected Exogenous Androgen Before Sexual Differentiation

ObjectiveIn our previous study, we found that exogenous androgen administered in the initial neonatal hours has effect on the sexual orientation and sexual behavior of female rat. In another study on these female rat, the volume of the sexual dimorphism nucleus in preoptic area(SDN-POA) and anteroventral periventricular nucleus(AVPV) were changed compare to the controls. Therefore, we were interested in the molecular biologic variation in these female rat's brain, especially in the hypothalamus proteome。In this study, we aimed to identify protein molecules in the hypothalamus in the same rat as that reported in the previous study.Methods1. Neonatal female SD rats were randomly divided into two groups:experimental group and control female group. Four neonatal male SD rats were control male group. Twenty-four hours after birth, all animals were subjected to intraperitoneal injection of testosterone propionate as experimental group or aseptic oil as control. The rats were sacrificed 90 days after the injection and the brains were collected.2.2-DE were performed in order to establish profiles of proteome from rat hypothalamus.3.2-DE followed by MALDI-TOF-TOF mass spectrometry was used to identify proteins differentially expressed in rat hypothalamus from experimental group as compared to normal control group. Results11 differential spots were cut off from the Silver stained gel, and 9 of the spots were identified, which were Dihydropyrimidinase-like 3 (DPYSL3). heterogeneous nuclear ribonucleoprotein K(hnRNP K), Profilin2, Triosephosphate isomerase 1(Tpi 1). Carbonic anhydraseⅡ(CAⅡ), Annexin A3, Protein disulfide isomerase associated 3 (PDIA3), Creatine kinase-B and Secernin 1.Conclusion2-DE combind wiith MALDI mass spectrum was improved to be able to identify the differential expression proteins in rat hypothalamus. These proteins may play an important role in sexual differentiation and orientation.