@ARTICLE{Mozafar, author = {mozafar, ahmad and keshavarz, mojtaba and zareian, parvin and Johary, Habiboalah and kargar jahromy, hossein and Hoseini, Shirzad and }, title = { The effect of immobilization stress on the HPG axis (hypothalamic - pituitary - gonad) hormones and the number of spermatogonia}, volume = {3}, number = {3}, abstract ={Background & Objective: Stress has different effects on the living organisms. In this study the effect of immobilization stress the HPG (hypothalamic - pituitary - gonad axis) hormones secretion and the number of spermatogonia was studied in adult male rats Materials & Methods: 30 male rats were divided into 3 groups. The Control group: who were not exposed to any kind of stress, and two experimental 7 and 14 day groups which respectively received 2 hours of immobilized stress over 7 and 14 day stress periods, blood samples were collected directly from the heart of the animals, Hormones GnRH, LH and testosterone levels were measured by ELISA. The number of spermatogonia in the testes of adult male rats were counted. We used ANOVA and Duncan's test results in p ≤0.05 for statistic analyze test. Results: The results showed that immobilization stress significantly decreased concentrations of GnRH and testosterone hormones compared with the control group. Also the 14-day immobilization stress caused a significant reduction in spermatogonia cells. Conclusion: The results of this study indicate that the inhibitory effect of immobilization stress on the HPG axis may also cause negative effects on the spermatogenesis process. }, URL = {http://jabs.fums.ac.ir/article-1-225-en.html}, eprint = {http://jabs.fums.ac.ir/article-1-225-en.pdf}, journal = {Journal of Advanced Biomedical Sciences}, doi = {}, year = {2013} }