Parviz Tajik - Department of Clinical Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
Hesam Kohsari - Department of Clinical Sciences, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran
Babak Qasemi-Panahi - Department of Animal Sciences, Faculty of Agriculture, University of Tabriz, Tabriz, Iran.
Iraj Sohrabi-Haghdoost - Department of Pathology, Faculty of Veterinary Medicine, Science and Research Branch, Islamic Azad University, Tehran, Iran

Identification of exogenous factors affecting spermatogonial stem cells (SSCs) proliferation in vitro, provides worthy ways to study the basic biology of the cells. The aim of this study was to investigate the effects of a GnRH analogue (alareline acetate) on SSCs colonization in short-term co-culture with sertoli cells. Five, three-month old Holstein male calves were used to isolate spermatogonial and sertoli cells. Testicular germ cell collection was made by enzymatic digestion methods. The cells were co-cultured in a 15 day period and in vitro effects of various doses (0.5, 1,2 and 4 μg/ml) of GnRHa on SSCs colonization were assessed. Effects of GnRHa on SSCs proliferation were dose dependent. In conclusion, it was demonstrated that 1 μg/ml GnRHa was the optimum dose for SSCs colonization in comparison with control group. The highest treatment dose (4 μg/ml GnRHa), negatively affected SSCs colonization in comparison with control group

GnRH, Calf, Spermatogonial stem cell, Sertoli cell, Co-culture