Rat sperm count changes at early stages after hemic hypoxia

Correspondence: Ekaterina Pavlova Institute of Experimental Morphology, Pathology and Anthropology with Museum, BAS, Acad. G. Bonchev Str., Bl. 25, 1113 Sofia, Bulgaria. Tel.: +359 2 979 2336 e-mail: [email protected] ABSTRACT Sodium nitrite (NaNO2) is an inorganic salt with various industrial applications. In the circulation NaNO2 oxidizes hemoglobin to methemoglobin, which is incapable of transporting oxygen and can cause hemic hypoxia. Recent studies have shown that hypoxia affects testicular functions. In this respect, the aim of the present study is to investigate the effect of NaNO2-induced hemic hypoxia on the sperm count in mature rats. The experiments were carried out on four-monthold male Wistar rats. Sodium nitrite was administered intraperitoneally at 50 mg/kg body weight. Treated animals were sacrificed at different time intervals (1h, 5h, 24h and 48h) following the administration. Testes and epididymides were sampled, weighed and embedded in paraffin using routine histological practice. Spermatozoa were isolated from both vasa deferentia and counted. Reduction in the sperm count was observed in all experimental groups which was significant 1h (30%), 5h (47%) and 48h (28%) after NaNO2 administration. These changes may be indicative of impaired spermatogenesis. The gonado-somatic index (calculated as a ratio of testis weight to body weight) was elevated in the first hours (1h, 5h) and returned within the normal range at later stages. The elevated index could be due to increased testicular fluid volume which may be associated with vascular permeability and disturbances of water-salt balance and hypothalamo-hypophysial-gonadal axis. Future studies would elucidate if NaNO2-induced quantitative changes in the testicular structure are supported by histopathological findings.