Aryl Phosphate Derivatives of Bromo-Methoxy-Azidothymidine: DISCUSSION(2)
Physiological fertilization depends on the ability of the ejaculated sperm to swim, bind the zona pellucida, and penetrate the egg, all of which abilities are primarily dependent on sperm motility. The mechanisms by which spermicidal AZT derivatives affect sperm motility are not fully understood; however, their spermicidal activity differed from that of detergent-type spermicides. The fact that spermicidal AZT derivatives were not permeable to PI, as well as the intactness of the plasma membrane and acrosomal membranes observed after several hours of exposure to these drugs, suggested that these spermicidal AZT derivatives immobilize sperm without membrane disruption as confirmed at the ultrastructural level using HR-LVSEM, which reveals the true surface of a cell in its exposed state. Buy Advair Diskus Online
These properties of AZT derivatives differ from those of currently used spermicides, N-9 and gramicidin, which exert their effects via a detergent-like ability to damage the sperm membrane, perturb its conformation, and destroy its semipermeable nature, thereby impairing the sperm motility and egg-fertilizing functions. Because of their nonspecific membrane-disruptive properties, such vaginal spermicides have been shown to damage the cer-vicovaginal epithelium, as well, which may lead to a lower degree of protection from STD. A vaginal contraceptive that does not elicit any of the nonspecific membrane toxicity characteristic of detergent-type contraceptives would be desirable.