Effects of percoll washing and glycosaminoglycans on the lysophosphatidylcholin induced acrosomal reaction in stallion

Abstract

The present study was conducted to investigate the effects of skim milk glucose (SMG), percoll and Bracked and Oliphant medium supplemented with BSA (BO-BSA) washing and glycosaminoglycans treatments (GAG) on lysophosphatidylcholin (LPC)-induced acrosome reaction (AR) in stallion spermatozoa. Freshly collected semen was washed with SMG (300 g for 10 min), percoll (700 g for 30 min) and BO-BSA (300 g for 10 min). Part of the semen after each washing step was treated with LPC to asses the rate of AR. After SMG, percoll and BO-BSA washing, the spermatozoa were cultured with in 5 different concentrations of GAG (chondroitin sulfate; CS and heparin; 0, 3, 10, 30, 100 μg/ml) for 0, 1.5, 3 and 6 h at 38.5° C in 5% CO2 in air. The LPC-induced AR in fresh spermatozoa after washing with SMG, percoll and BO-BSA were 0.8%, 3.0%, 13.4% and 18.0%, respectively. A significant difference in the rate of AR was observed before and after percoll washing (Plt;0.05). The LPC-induced AR rates after CS and heparin treatments were 14.7-20.8% and 15.3-19.5%, respectively. No relationship was observed either with the concentration of GAG or culture time on the percentage of AR spermatozoa. Results of the present study indicate that the percoll and BO-BSA washing can potentiate the LPC induced AR in stallion spermatozoa. Moreover, CS or heparin may not be useful in inducing AR in stallion spermatozoa.