Effect of spinal cord injury on the testis ultrastructure

The relationship between spinal cord injury and testicular atrophy and impairment of spermatogenesis in still not fully known. The present study was carried out in order to obtain ultrastructural effects of thoracal spinal cord injury on the testis.Thirty adult male Wistar rats weighing between 250 and 300 g were used. Animals were divided into 6 groups each containing 5 animals. The first group was used as intact control group. The remaining 25 rats underwent spinal cord injury at thoracal 7-9 levels. After the operation, the incision was sutured and the animals were kept under standard conditions. Testicular tissues were taken from rats of 2th, 3th, 4th, 5th, 6th groups respectively on the 1th, 3th, 7th, 14th and 28th days following the operation. Also blood samples were obtained for hormone analysis. Testicular tissue pieces were processed for electron microscopy and examined with Jeol JEM-1400 transmission electron microscope.Electron microscopic examination of the testis from 1 day after operation revealed normal ultrastructure. After 3 days, Sertoli cells exhibited dilated smooth endoplasmic reticulum cisternae, abundant lipid droplets and lipofucsin granules. Most of the Leydig cells also contained dilated smooth endoplasmic reticulum cisternae forming variously sized vacuoles. Interesting ultrastructural changes were observed in testicular tissue on the 7th day. Abundant lipid droplets, dilated smooth endoplasmic reticulum cisternae and cytoplasmic lytic areas were encountered in Sertoli cells. Furthermore, enlargement of intercellular area between the spermatogonia, abnormal acrosome formation of the spermatids and thickened membrana propria were also observed. On the other hand, the most prominent fine structural alterations were seen on the 14th and 28th days. Most of the Sertoli cells revealed pyknotic nuclei, abundant lipid droplets and numerous electron dens bodies and variously sized vacuoles. Moreover, many of the tubules exhibit abnormal spermatids and alterations of the membrana propria include ondulated basal lamina and excessive collagen fibers.Testicular ultrastructural changes in the thoracal 7-9 level of spinal cord injury have been documented in detail in this study. It is widely accept that the acute effect of spinal cord injury on the spermatogenesis due to hormone deprivation, whereas neurogenic mechanisms affect atrophy of seminiferous tubules and abnormal spermatogenesis during the chronic phase of the injury. These ultrastructural alterations can lead to impairment of fertility that may caused by the neurological injury at the level of thoracal spinal cord of the brain-testicular axis needs further investigation.