Ejaculatory Duct Obstruction Affects Seminal Vesicle Contractile Efficacy and Smooth Muscle Ultrastructure in a Rat Model

Abstract

The purpose of this study was to investigate the effects of ejaculatory duct obstruction (EDO) on contractile efficacy, smooth muscle ultrastructure, and α1A and M3 receptors of rat seminal vesicles (SVs). A total of 48 male rats, aged 14-15 weeks, were randomly divided into three groups, namely, the control, complete EDO, and partial EDO. SV tissues were collected at 4 and 8 weeks postoperatively for further experiments. Results revealed a marked reduction in SV contractile efficacy over time following obstruction in the complete EDO group. The contractile force and frequency decreased and increased in the partial EDO group at week 4, respectively, whereas contractile efficacy significantly reduced at week 8. Moreover, obstruction resulted in significant downregulation in expression of α1A and M3 proteins and mRNAs in rats from the complete EDO group over time. Rats in the partial EDO group initially exhibited an increase followed by a decrease. Analysis of the ultrastructure of SV smooth muscles confirmed the above changes. In conclusion, complete EDO can lead to a progressive decrease in contractile efficiency of SVs. On the other hand, partial EDO can first compensate for the contraction of SVs and gradually decompensate afterwards.