Study of histological changes in the testes and sperm parameters of the mice after contusive spinal cord injury

Infertility is one of the major problems associated with contusive spinal cord injury (SCI). Sperm qualities such as low viability, low motility, and increase in abnormal morphology are complications arising from infertility following SCI. The purpose of this study was to evaluate testicular changes and spermatic parameters after contusive spinal cord injury in the mice.

In this experimental study, a total of 75 adult NMRI mice were divided into 3 groups: SCI, sham, and control.In the SCI group, following laminectomy without any damage to dura matter, the spinal cord was hit with a 2 gr weight dropped from a distance of 2.5 cms onto the exposed dura matter in the 9th thoracic vertebra while the control group was not exposed to any type of damages or medications. In the sham group, only laminectomy was performed. The epididymal sperms were prepared after one day, one, two, four, and six weeks. The data was analyzed by means of SPSS software using one-way ANOVA statistical test.

The present study demonstrated that SCI is effective on the parameters of sperm. On the first day, none of the parameters were significantly different with those in the control group. In the 1st and 2nd weeks significant reduction in sperm morphology and viability rates was observed in the experimental group (P<0.05) compared to the control group. All parameters of sperm had significant changes in the 4th and 6th weeks compared with the control group (P<0.05). Besides, histological change was observed in the testes tissue, integrity of seminiferous epithelium basal membrane was reduced, and testicular capsule thickness increased.

It was shown that spinal cord injury decreases motility, viability, and changes morphology of the mice sperm.