The Effect of Cadmium and Selenium on The Testicular Function and Tissue Injury in Male Rats

The effect of the sub lethal dose of cadmium chloride CdCh 7mglkgl body I weight ) was investigated on the testis and some sperm parameters in rats .. To evaluate the effect of cadmium exposure as CdCh, was orally administered to mature male rats( 250-300g I body weight) for 28 days and the effects on the sperm count , sperm motility , sperm abnormality , sperm death percentages and testes weight, as well as testicular histology were observed. To evaluate the beneficial action of Selenium against Cadmium chloride-induced reduced sperm count and sperm abnormalities and testes injury in albino rats , an additional two groups of rats were treated for same period with SeCiz 8m/kgl body •Presented at the first conference on Biology , University of Mosul ,college of Education , 4-5 September 2007 The Effect of Cadmium and Selenium .... weight ) and Cd Se combination · respectively to determine the reversibility of Cd-induced changes The sperm counts, sperm motility, sperm abnormality and sperm ) death percentages were significantly decreased following 28th day of CdCh treatment, but were unaffected by Se and CdSe exposures. The testicular, epididymis, prostate and seminal vesicle weight were noticeably reduced with Cd-treatment as compared to control. The changes caused by cadmium are mostly recovered by Se administration. Cadmiu·m chloride exposure injures the fertility parameters of male rats and the effects are reversible due to Se supplementation. On the other hand, co-administration of Se at the above mentioned dose to Cadmium treated rats led to the most significant decline in testes tissue damage alorig with elevated ·sperm count and . reduction in the percentage of abnormal spenn population. The protective action of Se and the antagonistic effect of both Se and Cadmium induced testes tissue damage are discussed. Introduction The roles that heavy metals play in the etiology of reproductive pathology debated for several decades [1]. Few studies were undertaken the effects of different inorganic and organic oxidant substances on the rats testes were available. Recently the effects of these oxidants substance on the testicular gametogenic activities in relation to oxidative stress in rats were investigated [2] and [3] . Results of these studies demonstrated the · treatment by different oxidant substances resulted in significant reduction in relative organs weight ( testes , epididymis , prostate and seminal ves icle ) in which subsequently affect the sperm production and motility .Moreover, Latchoumycandane, et al ,rJ results showed that the coadministration of the antioxidant ( vitamin E ) , prevented significant changes in the antioxidant systems in the epididymis and Epididymal sperm and prevent alteration in sperm count and motility. Cadmium is an extremely toxic environmental contaminant that causes the production of reactive oxygen species( ROS )such as hydroxyl radicals , superoxide anions , nitric oxide and hydrogen peroxide[ 5] , cadmium induced oxidative stress is thought to play an important role in the pathogenesis of numerous degenerative diseases[6] . There are several hypotheses that suggest how reduced male fertility may result from incorporation of heavy metals into testes [7]. One hypothesis suggests that the presence of highly bound cadmium may prevent normal disulfide bond formation within and among protamines during final stage of sperm maturation. The disruption of this process may lead to lethal effect(8] . However, the information suggesting the involvement of heavy metals in the etiology of reduced male fertility has been elucidated.