Detection of 25-kDa Anti-Agglutinin in Epididymal Plasma and Spermatozoa Collected from Various Regions of Boar Epididymis.

Abstract

Distribution of the 25-kDa epididymal anti-agglutinin for spermatozoa was examined by the Western blotting technique in fluid collected from boar rete testes and epididymides. Fluid was collected from the rete testes and various regions of the epididymis, and then plasma and sperm extracts were prepared. Antiserum was raised against the anti-agglutinin, and specific antibody was purified from it. In the plasma, a reaction between the anti-agglutinin and purified antibody was first observed in the proximal corpus epididymidis and became stronger in the more distal regions. In extracts from washed spermatozoa using the original sample buffer, anti-agglutinin was detected between the proximal corpus and the distal cauda and more strongly in the distal corpus. A thorough washing of spermatozoa on a discontinuous Percoll gradient brought about only minor changes in the detection pattern of anti-agglutinin. However, in samples extracted from washed spermatozoa using a modified sample buffer containing twofold detergent and twofold 2-mercaptoethanol, a stronger reaction was observed between the anti-agglutinin and purified antibody in the distal cauda than in the distal corpus. These results indicate that free or loosely sperm-bound anti-agglutinin increases in the corpus and cauda epididymides. It is also suggested that solubility of the anti-agglutinin associated with spermatozoa in the original sample buffer decreases in the cauda epididymidis.