Cloprostenol and pregnant mare serum gonadotropin promote estrus synchronization, uterine development, and follicle-stimulating hormone receptor expression in mice

This study investigated the effects of pregnant mare se­rum gonadotropin (PMSG) and cloprostenol (CLO) on estrus induc­tion and synchronization, uterine development, and follicle-stimulating hormone receptor (FSHR) expression in mice. A total of 105 Kunming pre-puberty mice were divided into seven subgroups. Three PMSG sub­groups were injected intraperitoneally with 10, 20, and 40 IU PMSG twice (on days 0 and 4), and three CLO subgroups were injected intra­peritoneally with 10, 15, and 20 μg cloprostenol acetate twice (on days 0 and 4). The results showed that 93.33 and 66.67% of synchronized mice displayed estrus within 18.68-37.59 h following CLO and PMSG exposure, respectively. Estrus numbers, estrus onset time, and estrus rates in CLO and PMSG groups were greater than in control groups (CG) (P < 0.05). Uterine weights of the PMSG group were higher than that of CLO and CG groups, and the uterine horn longitudinal diameters in experimental mice were greater than CG. Expression levels of FSHR proteins in CLO and PMSG groups increased slightly when compared to CG. In conclusion, CLO and PMSG administration did not clearly af­fect the expression of uterine FSHR proteins in mice. Moreover, PMSG and CLO treatments synchronized estrus and enhanced the uterine de­velopment of mice. The efficacy of CLO on estrus synchronization was greater than PMSG, and the effects of PMSG on uterine development were stronger than CLO. These results have important significance re­garding the modulation of animal reproductive functions.