This study used 50 male BALB/c mice divided into three groups [20 in each of test groups A and B and 10 in the control group C]. Group A and group B were exposed to total diesel exhaust [TDE].
The TDE exposures were performed in a cubic wooden box chamber [side length 50 cm] filled with TDE from a diesel fueled car. Group A was moved to the diesel filled chamber and exposed once a day for 30 minutes and group B was moved to the filled chamber and exposed once a day for 60 minutes. The control group was similarly manipulated for 60 minutes without filling the chamber with TDE. The experiment was carried out six days a week for 120 days. Four animals from group A and six animals from group B did not survive to the end of the experiment while the control animals did not have mortalities. Five of the remaining mice from each test group and 2 controls were sacrificed on the 40th day and on the 80th day. Remaining six mice in group A and four mice in group B and six mice from group C were sacrificed at the end of the experiment [120th day]. Testes and vasa efferentia were removed, testes were prepared into sections for histological, immunohistochemical staining and testicular biopsies [5 mg each] were used for Western blotting experiments to detect acrosomal proteins. Vas spermatozoa were prepared as smears for immuno-histochemical study. Down regulation of spermatogenesis reflecting structural damage of the seminiferous tubules was observed in animals sacrificed on the 40th day, this was progressive with time of exposure as seen in samples obtained on the 80th and 120th days The dependence on exposure time was also clear from comparison of sections from groups A and B, Severe oligozoospermia was detected in group A by the end of 80th days and in group B by the end of the 40th day. By the end of the experiment [120 days], the seminiferous tubules from the testes of the two test groups A and B were containing Sertoli cells only. Immunohistochemical staining of testicular sections and vas sperm suspensions using monoclonal antibodies for internal acrosomal proteins revealed a concomitant ultrastructural damage of spermatozoa in the form of defective or absent acrosome and increased proportion of abnormal sperm head morphology. The progressive decrease of sperm and spermatid -specific proteins in testicular biopsies was observed in the immuno blots. It is concluded that exposure to diesel exhaust has a massive reproductive toxicity in male mice manifested by suppression of spermatogenesis and abnormal ultra structures of vas spermatozoa. Also, the reproductive toxic effect of diesel exhaust exposure is both dose [exposure time] -dependent and duration [repeated exposures] -dependent
Abul fetouh Alenany ,Aisha Ibrahim Maklad ,Mona Mohammed Attia ,
Reproductive toxic effects in the testes of BALB/c mice exposed to total diesel exhaust,
Zagazig J. Forensic Med. Toxicol. 2006;
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