Restraint stress and lead-induced reduction in progeny output by male rats

We investigated whether restraint stress interferes with lead-induced suppressed fertility in rats. Male Wister rats (weighing 200 ± 10 g in the beginning of the experiment) were subjected to either restraint stress (5 hours/day) or exposed to lead (0.15%) or both for 60 days. To assess the fertility, control and experimental males were cohabited with sexually mature normal females. No significant changes (p>0.05) were observed in the body weight gain of experimental males. Similarly, no changes (p>0.05) were observed in the mating index. In contrast, there was a significant decrease (p<0.05) in fertility rate, measured by counting live foetuses in the uterus of normal females mated with males exposed to either restraint stress or lead. In rats mated to males subjected to both restraint stress and lead treatment, a significant decrease (p<0.05) in live fetuses was observed as compared to rats mated with lead alone exposed males.These data demonstrate that adult male rats exposed to either restraint stress or lead significantly decreased fertilization capacity and stress potentiates the reproductive toxicity of lead.