35 Document heading doi: Histomorphological evaluation of mice testis after co-exposure to lead and cadmium Maria de Lourdes Pereiraa * Neidy Varela Rodriguesa, Fernando Garcia e Costab a Department of Biology, CICECO, University of Aveiro, 3810-193 Aveiro, Portugal b Department of Morphology and Function, CIISA, Faculty of Veterinary Medicine Technical University of Lisbon, Portugal ARTICLE INFO ABSTRACT Article history: Received 10 November 2011 Received in revised form 15 January 2011 Accepted 15 March 2012 Available online 20 April 2012 Keywords: Lead cadmium testis spermatogenesis *Corresponding author: E-mail address: mlourdespereira@ua.pt Telephone: +351 234 370770 Fax: +351 234 372587 1. Introduction Exposure to the myriad of hazardous substances at both environmental and occupational settings may severely disrupt semen quality, and fecundity. Elegant studies evidenced the deleterious effects of some chemicals such as heavy metals, solvents, pesticides on male reproductive function [1-6] . Attention was focussed on spermatogenesis, a complex process which is easily adversely affected by pollutants. Among the innumerable environmental contaminants, lead and cadmium compounds deserve special concern, since they target multiple organs and systems in both human and wildlife [7] . In fact, cadmium and lead were classified as human carcinogens by the I nternational Agency for Research on Cancer [8-9]. I n addition, reprotoxic effects of these compounds were largely reported in the literature. For example, adverse effects of lead chloride on sperm parameters of mice were described [10] . Although sperm physiological parameters such as motility, morphology and acrosome status were altered, no significant genotoxic effects were detected in this report. Recently, El Shafai and co-workers [11] evidenced severe testis alterations on albino rats after prolonged lead exposure, using light and electron microscopy studies. Cadmium is also a known endocrine disruptor compound, interfering on the synthesis and the regulation of some hormones in both females and males [12] . The toxic effects of cadmium on the reproductive system and underlying mechanisms were reported [13] . In those papers, testicular changes have been described on animal models at different stages of growth and maturity. Disruption of the blood–testis barrier by Cd due to adverse effects on cell adhesion, oxidative stress, and necrosis at higher experimental doses Objective: The present study investigates the effects of co-exposure to lead and cadmium on mice testis using histomorphological approach. Methods: Male mice were subcutaneously injected with lead chloride on day 1, and cadmium chloride on day 2 (74mg and 1mg/kg body weight, respectively), and kept for 24h. Vehicle control group was also considered. Mice where then sacrificed and testis collected and weighed. Samples were fixed on Bouin´s solution and processed for histology. The diameter of seminiferous tubules in both groups was calculated using software based on deformable models (SNAKE). Results: The combined exposure of Pb and Cd induced degenerative changes in testis, namely, wavy contour of seminiferous tulules, germ cell loss, and release of immature cells into the lumen. Atrophy of seminiferous tubules was seen in this group, confirmed by a significantly decrease in the diameter. Conclusions: Cumulative effects of PbCl2 and CdCl2 may have disrupted the blood-testis barrier causing then, the histopathological lesions within testis. Asian Pacific Journal of Reproduction (2012)35-38 Asian Pacific Journal of Reproduction Journal homepage: www.apjr.net