Methods
Testes of neonate Balb/c mice were vitrified- thawed under standard condition with or without the addition of 100 μM melatonin to both vitrification and thawing solutions. Subsequently, Vitrified-thawed whole testes were digested under standard condition and spermatogonial stem cells type A were separate in the suspension with CD90.1 (Thy1.1(+)) micro beads. Extraction of RNA and synthesis of cDNA was performed. Expression levels of apoptotic genes (Fas, P53, BCL-2 and BAX) were determined using Real-time PCR.