Ascaris suum: Electrophoretic characterization of reproductive tract and perienteric fluid polypeptides, and effects of seminal and uterine fluids on spermiogenesis

Abstract

Fluids isolated from the testis, seminal vesicle, uterus, and pseudocoelomic cavity of Ascaris suum were characterized using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and measured for protein concentration, pH, and osmolarity. The testis and seminal fluids display much homology and share major polypeptide components having molecular weights of 15,000 and 35,000. A cytoplasmic extract of spermatids from the seminal vesicle exhibited a banding pattern nearly identical to that of testis fluid. The seminal fluid has unique major components of 57,000 and 150,000, and seminal fluid from individual worms showed differences in major band concentration and distribution of minor components. The uterine fluid has major polypeptides of 14,000, 16,000, 66,000, 74,000, 120,000, and 140,000, and exhibits more similarity to the perienteric fluid then either the seminal or testis fluids. Electrophoretic comparisons of four uterine regions revealed nearly identical banding patterns although somewhat higher concentrations of four major components occurred in certain segments. The male and female perienteric fluids have major bands at 40,000, 120,000, and 140,000, and the female fluid has more intense minor components of 90,000 and 115,000. Perienteric fluid from individual worms differed only in minor band distribution. The reproductive fluids have numerous minor components mostly from 20,000 to 70,000, while the perienteric fluid minor bands are mainly located in the 80,000 to 120,000 range. The pH of the seminal fluid (6.5) differs from that of the uterine fluid (7.7), and both seminal and uterine fluids are of lower osmolarity than the perienteric fluid. In vitro studies demonstrate that uterine fluid does not induce spermatid transformation into bipolar, ameboid spermatozoa, while the seminal fluid induces only lipid granule coalescence in either seminal vesicle or terminal testis spermatids.