Photoperiod Regulates the Expression of GPx-5 in the Epididymis of Cricetulus barabensis through Androgen

For animals that breed seasonally, photoperiod is a key factor in controlling their behavior. Epididymal function is highly dependent on androgen. However, the effects of photoperiod on epididymal function and the regulatory mechanism of androgen in this process have not yet been reported. This study examined the effects of different photoperiods on androgen contents and the expression patterns of 5α-reductase, AR, and GPx-5 in the epididymis of Cricetulus barabensis to explore the role of androgens in photoperiod regulation of epididymal function and its mechanism in antioxidant stress. The results showed that in the caput epididymis, androgen content decreased with the shortening of light time, and the mRNA and protein levels of 5α-reductase 1 and androgen receptor (AR) in the long photoperiod (LP) group were significantly higher than those in the short photoperiod (SP) group. In the cauda epididymis, androgen content and the mRNA and protein level of GPx-5 were the lowest in the medium photoperiod (MP) group. In conclusion, these results suggest that androgens affected by the photoperiod may regulate the expression of GPx-5 through the androgen/AR pathway. The findings of this study will help to understand the physiological and biochemical status of the epididymis of seasonally breeding animals under different photoperiods.