The gene expression of superoxide dismutase and the changes of the ultrastructure of rat testis after exposed to electromagnetics

Abstract

The aim is to study the expression of superoxide dismutase (CuZnSOD, MnSOD) and the changes of ultrastructure in rat testis after electromagnetic radiation (EMR) so as to investigate the mechanisms of EMR effect on procreation. As an in vivo model, male SD rats were used. Rats were exposed to the field of electromagnetics. By reverse transcription-polymerase chain reaction (RT-PCR), manganese SOD (MnSOD) and copper/zinc SOD (CuZnSOD) mRNA in the testis have been tested and the testis samples were prepared for transmission electron microscopy to observe the ultrastructure at 6h, 12h, 24h and 48h after radiation. In rat testis, MnSOD mRNA expression decreased at 24h and CuZnSOD mRNA expression did not change after radiation; the ratio of MnSOD/CuZnSOD decreased at 24h after radiation. These were some degree injuries in the testis at different time after radiation, the testis damage at 24h was more serious than that at other times after radiation. At 24h after exposure, the chromatin was gathered in the border and the endoplasmic reticulum (ER) was dilated and vacuolated in interstitial cells, spermatogonium cells of rat testis. The changes in sustentacular cells was more serious than the other cells. The results showed that the MnSOD gene expression was decreased and the ultrastructure of rat testis were damaged after exposure to electromagnetics. These changes may induce the other effects, and the change of MnSOD expression might reflect a defensive mechanism of rat body against oxidative stress. If these changes would not regain in time, they may cause worse effects. Thus, EMR could induce some changes in the testis of rats so as to alter the procreative function.