Modifications of sperm proteins leading to acquisition of fertilizing ability

Abstract

Mammalian spermatozoa acquire their fertilizing ability following release from the seminiferous tubules, as they transverse the epididymis, the female tract and the egg investments. We have examined changes occurring in the distribution of antigens of rat spermatozoa during epididymal maturation and after ligation of the caput epididymis by using immunocytochemistry at the light microscopy and at the electron microscopy (EM) levels.Spermatozoa were collected from the test is and different segments of the epididymis. To obtain aging of sperm in vivo, male rats were operated and one side of the epididymis was ligated at the caput and corpus junction. Spermatozoa were washed, and divided into 4 tubes, and treated as follows: 1. no treatment; 2. permeabilization by freeze thawing; 3. Trypsin; 4. NP-40;. Sperm samples were washed and the nincubated for 30 min with monoclonal antibodies. Monoclonal antibodies were raised in mice against antigens on cauda sperm of rats.