Spermatozoa Repellent As A Contraceptive

Early report by Kopp et al. have demonstrated that p-nitrophenyl-glycerol (PNPG) is an effective antiswarming agent in Proteus and that this inhibition may have been caused by PNPG interfering with the negative chemotaxis mechanism in the organism. With an inverted capillary assay, designed to test the motility response of rat epididymal spermatozoa to various suspending conditions including those exposed to chemical gradient, PNPG was shown in this study to exhibit an inhibitory effect at slightly higher than 10(-5) M. Moreover, this inhibitory effect appears to have stemmed from spermatozoa being repelled by PNPG as indicated by the observation that significantly less spermatozoa swim into a gradient of PNPG. The possibility of using spermatozoa repellents as contraceptives is discussed.