Germ Cell Apoptosis In The Contralateral Testis Following Lateral Testicular Torsion: Involvement Of The Fas-FasL And Delay-type Hypersensitivity (DTH)?

Objective The aim of this study is to determine the mechanism of effecttesticular torsion on the contralateral testis , the involvement of the Fas-FasL system and delayed type hypersensitivity in the process.Methods: The testicular torsion was created by surgery in SD rats. CsA wasadministered orally for 10 consecutive days before and after testicular torsion .Apoptosis was studied by light microscopy and TUNEL techniques. The expression of Fas-FasL was detected by immunohistochemistry and Real-time PCR. DTH was assessed by measuring delayed footpad reaction to autologous testicular celll.Results: In rats with detorsion or orchectomy following 6 hr testiculartorsion , the number of apoptotic germ cells and the expression of the Fas-FasL in the contralateral testis is increased at 2 weeks and 4 weeks .The rats with testicular torsion had less number of apoptotic germ cells and less expression of the Fas-FasL after CsA administered orally. DTH was induced in the rats with detorsion or orchectomy,but not in the ratswith testicular torsion and CsA administered orally. Conclusion: l)Testicular torsion cause apoptosis of germ cell to thecontralateral testis. This damage can be abatement by administration of CsA.2) Apoptosis of germ cell induced by testicular torsion is mediated by Fas-FasL system, whose expression can be suppressed by CsA.. 3) Testicular torsion induced DTH ,which can be inhited by CsA. DTH inducedby testicular torsion may alter the expressionn of Fas-FasL throughtincreasing cytokine in testis.4) CsA could be used to prevent damage of spermatogenesis after testiculartorsion take place in clinic, but further research and clinical experiment isrequired in the future.