摘要 : Cryopreservation induces partially irreversible damage to sperm membranes as a result of membrane destabilization. Membrane damage after freezing might be linked to the modification of the membrane fluidity before freezing. Methyl... 展开 Cryopreservation induces partially irreversible damage to sperm membranes as a result of membrane destabilization. Membrane damage after freezing might be linked to the modification of the membrane fluidity before freezing. Methyl beta cyclodextrin (m beta CD) was found to selectively extract cholesterol from the plasma membrane and therefore increase membrane fluidity. The present study aimed at investigating the effect of adding m beta CD to the Tris-based diluent on the freezability and in vitro fertilizing potentials of buffalo spermatozoa. Buffalo semen was collected, evaluated and extended in Tris-based extender supplemented with different concentrations of m beta CD (Experiment 1) or with cholesterol-3-sulfate and/or m beta CD (Experiment 2). Semen was examined post-thawing to evaluate their freezability, cholesterol content and in vitro fertilizing potentials. It was shown that addition of m beta CD to the semen diluent before freezing significantly improved the freezability and fertilizing potentials in a dose dependent trend. Addition of 5 mg/ml m beta CD significantly increased (P<0.01) post-thawing motility, viability index and maintained the acrosomal integrity (57.50+or-2.50, 157.50+or-8.29 and 12.00+or-0.81%, respectively) compared to the control semen (41.25+or-1.25, 105.55+or-2.88 and 18.25+or-2.46%, respectively) and significantly increased (P<0.05) the development to morula and blastocyst stage (24.44 and 15.56%, respectively) compared to the control semen (6.38 and 2.13%, respectively). Moreover, 5 mg/ml m beta CD could resolve the drastic effect of cholesterol-3-sulfate on buffalo semen freezability and in vitro fertilizing potentials. In conclusion, addition of methyl beta cyclodextrin to the semen diluent prior to freezing is an effective method that increases the cryosurvival and in vitro fertilizing potentials of buffalo spermatozoa. 收起