Fayed A H
Department of Physiology, Faculty of Veterinary Medicine, Alexandria University, Egypt.
Contraception. 1996 Mar;53(3):181-4. doi: 10.1016/0010-7824(96)00008-x.
The in vitro effect of PGF2 alpha and methylxanthines (theophylline and caffeine) on enzymatic release of bull epididymal spermatozoa was investigated. Epididymal spermatozoa were diluted with egg yolk citrate-based diluent to a concentration of 50 x 10(6) spermatozoa per ml. Aliquots were supplemented with PGF2 alpha at levels of 0, 300, 600 and 1200 micrograms/ml, theophylline or caffeine was added at levels of 0, 500 and 1000 micrograms/ml and incubated at 37 degrees C for 4 h. Spermatozoal motility was decreased with increasing level of PGF2 alpha and the activities of transaminases in the extracellular medium showed a continuous increase. Addition of theophylline or caffeine at both dose levels significantly increased the sperm motility; the activities of transaminases either were not significantly changed or were significantly decreased during the 4 h incubation. These results suggest that supplementation of bull spermatozoa with high levels of PGF2 alpha suppressed motility and induced sperm membrane damage and permeability. However, supplementation of bull spermatozoa with methylxanthines enhanced sperm motility and was not harmful to the integrity of the sperm membrane.
研究了前列腺素F2α（PGF2α）和甲基黄嘌呤（茶碱和咖啡因）对公牛附睾精子酶释放的体外作用。附睾精子用基于蛋黄柠檬酸盐的稀释剂稀释至每毫升50×10⁶个精子的浓度。将等分试样分别添加浓度为0、300、600和1200微克/毫升的PGF2α，添加浓度为0、500和1000微克/毫升的茶碱或咖啡因，并在37℃下孵育4小时。随着PGF2α水平的增加，精子活力降低，细胞外培养基中转氨酶的活性持续增加。添加两种剂量水平的茶碱或咖啡因均显著提高了精子活力；在4小时的孵育过程中，转氨酶的活性要么没有显著变化，要么显著降低。这些结果表明，向公牛精子中添加高水平的PGF2α会抑制活力并导致精子膜损伤和通透性增加。然而，向公牛精子中添加甲基黄嘌呤可提高精子活力，且对精子膜的完整性无害。
