Electrophoretic modification of sperm plasma membrane by ventral prostate secretion in golden hamsters

Plasma membrane proteins were extracted either from epididymal spermatozoa after incubation with ventral prostate gland secretion or from spermatozoa recovered from uteri of females mated with surgically treated males belonging to the following groups: TX (excision of all accessory sex glands, ASG), VPX (bilateral excision of ventral prostate), VP (bilateral excision of all ASG except the ventral prostate), and SH (sham-operated). Incubation of spermatozoa with ventral prostatic secretion resulted in an 11-fold increase in glycoprotein content of the plasma membrane, but total protein concentration remained unchanged. The in vivo study indicated that interactions of ASG secretions and spermatozoa were complicated by the presence of uterine secretions. Glycoprotein content was reduced in the presence of ventral prostatic secretions. SDS-PAGE profiles showed that both uterine and ASG secretions could modify proteins on the sperm surface. Enrichment of a 25-kD subunit was apparently effected by uterine secretions and further promoted by combined secretions of the ampullary gland, coagulating gland, dorsolateral prostate, and seminal vesicle, but was reduced by the ventral prostate. A number of other protein subunits appeared to be specifically modified by the ventral prostate, while other ASG secretions were also shown to alter the effects of the ventral prostate on the sperm surface.