Studies On The Effect Of Lipopolysaccharide On The Expression Of Reproductive Hormone Receptors In Hypothalamus, Ovary And Oviduct Of Female Rabbits

Lipopolysaccharide (LPS) is the major component of gram-negative bacteria, which induces pathological response throughout the body similar to true gram-negative bacteria infection. Because of gram-negative bacteria infection, the normal animal reproduction activities were disturbed, which may attribute to lots of reproductive disorder diseases, such as decreases reproduction ability. In this study, LPS was used to minic the real gram-negative bacteria infection in female rabbits. Our aim is to explore the change of concentration of reproductive hormone in serum and the expression pattern or expression level of reproductive hormone receptors in hypothalamus, ovary and oviduct in response to LPS.Female rabbits (Aged:5-6 months) ear vein injected with LPS (0.5mg/Kg) or corresponding saline in control group. The blood sample, hypothalamus, ovary and oviduct were collected at O(non-treatment),1.5h,3h,6h and 12h after injection(n=4). The level of hormone in serum was measured by ELISA, and expression level or expression pattern of reproductive hormone receptors in hypothalamus, ovary and oviduct were analyzed by real-time PCR and immunohistochemistry.The results of ELISA indicate:In control group, the concentration of GnRH? FSH?P4 and E2 in serum with time-course is not significant difference(P>0.05); the concentration of LH after 3h and 12h post-injection is significant higher than that at 1.5h and 6h(P<0.05). In LPS group, the concentration of GnRH. FSH?LH?P4 and E2in serum with time-course is not significant difference(P>0.05). LPS group compared with the control group at the same time point indicates:the concentration of FSH is significant lower than control group after 3h of post-injection(P<0.05), the concentration of E2 is significant lower than control group after 1.5h,3h and 6h of post-injection(P<0.05).The results show, the concentration of FSH and E2 is significant decreased in response to LPS.The results of real-time PCR indicate:In control group, the expression of GnRHR in hypothalamus with time-course is not significant difference. However, the expression of GnRHR mRNA in.ovary after 1.5h post-injection is significant higher than that at Oh(P<0.05) and the expression of GnRHR in oviduct after 3h injection is significant higher than that at 6h(P<0.05). In addition, the expression of FSHR, LHR, PGR and PGRMC1 in hypothalamus, ovary and oviduct with time-course were not significant difference. In LPS group, the expression of GnRHR, FSHR?LHR?PGR and PGRMC1 in hypothalamus and ovary, and the expression of GnRHR?FSHR and LHR in oviduct with time-course were not significant difference. However, the expression of PGR in oviduct after 1.5h,3h,6h and 12h post-injection is significant lower than that at Oh(P< 0.05) and the expression of PGRMC1 in oviduct after 6h injection is significant lower than that at 0h(P<0.05). LPS group compared with the control group at the same time point indicates:the expression of FSHR?LHR and PGRMC1 in oviduct is significant lower than control group after 12h of post-injection, expression of PGR is significant lower than control group after 1.5h of post-injection. The results indicate, the transcription level of FSHR, LHR, PGR and PGRMC1 in oviduct is inhibited in response to LPS.The results of immunohistochemistry indicate:The expression of GnRHR protein in hypothalamus and primordial follicle oocyte is not response to LPS, the expression of GnRHR protein in oocyte of primary and secondary follicle, granulose and theca cell of secondary and tertiary follicle and epithelium of oviduct is up-regulation in response to LPS, and the expression of GnRHR protein in tertiary oocyte and musule layer of oviduct is up-or down-regulation in response to LPS. The expression of FSHR protein in primordial follicle oocyte is down-regulation in response to LPS, the expression of FSHR protein in oocyte of primary follicle, granulose and theca cell of tertiary follicle, epithelium and muscle layer of oviduct is up-regulation in response to LPS, the expression of FSHR protein in oocyte and granulosa cell of secondary follicle is not response to LPS, and the expression of FSHR protein in hypothalamus, oocyte of tertiary follicle and theca cell of secondary follicle is up-or down-regulation in response to LPS. The expression of LHR protein in hypothalamus, oocyte of primordial, primary and secondary follicle, granulose and theca cells of secondary follicle and muscle layer of oviduct is down-regulation in response to LPS, and the expression of FSHR protein in oocyte, granulose and theca cells of tertiary follicle, epithelium of oviduct is up-or down-regulation in response to LPS.