Seminal Vesicles: Development, Secretory Products, and Fertility

Abstract

The development of the seminal vesicle from the mesonephric duct is described. Particular attention is given to the recent biochemistry of seminal vesicle proteins. Proteins in the seminal vesicle fluid are few in number, may be insoluble at certain pH, and frequently form large macromolecular aggregates. Although not an absolute requirement for fertility, seminal vesicle fluid assists in a number of ways to insure fertility. A biochemical model is presented that demonstrates that CAMP dependent phosphorylation may be an important interaction between sperm and certain seminal vesicle proteins.Key Words: development, secretory proteins, seminal vesicle, sperm phosphorylation. INTRODUCTIONSeminal vesicles are secretory organs of the male genital tract found in certain eutherian mammals. The size, chemical composition of the secretions, and morphological characteristics of the seminal vesicles are variable, species ~p e c i f i c , '~.~* and dependent on androgens for embryonic development, growth, and secretory f~n c t i o n .~~.~~ EMBRYONIC DEVELOPMENTDuring embryonic development the seminal vesicles (and the epididymis and ductus deferens) are derived from the mesonephric or WolffianIn mice (on the 15th day of gestation) and rats (on the 16th day of gestation), there is a notable expansion of the epithelium of the lower aspect of the Wolffian duct. This marks the site where the seminal vesicle rudiment will bud off in later g e~t a t i o n . '~ Development of this tissue is dependent on testosterone secretion by the fetal testis. Testosterone prevents programmed cell death and stimulates growth and organogenesis of the mesonephric duct deri~ates.~' The onset of testosterone formation by the fetal testis occurs before male differentiation of the urogenital tract.8 The probable source of the steroid substrates (pregnenolone and progesterone) used in testosterone synthesis in the testis is the placenta or the adrenal gland.35Wolffian duct stabilization and morphogenesis of the seminal vesicle results from an androgen-dependent interaction between embryonic mesenchyme and epithelial tissues. l 6 Dur- In the neonatal rodent there are two peaks of seminal vesicle cell proliferation, from birth to approximately fifteen days of age, and just before puberty (twenty-five-thirty-five days). In the intervening time period there is a quiescent interval.25 The response of the seminal vesicles to androgen at puberty is enhanced by the neonatal exposure to androgens, an irreversible phenomenon known as imprinting.42 The biphasic response of the seminal vesicles seems to be the result of two populations of Leydig cells during development. One population appears during fetal life (secretes fetal testosterone) and the other arises during puberty.26 At birth the fetal Leydig cells undergo regression. The regression involves reversion of these cells to a less differentiated cell type rather than cell death. The tissue then enters the quiescent period.During the period of regression the testis secretes 5 alpha androgens (androsterone...

Effect of homologous and heterologous seminal plasma on the fertilizing ability of ejaculated bull spermatozoa assessed by penetration of zona-free bovine oocytes

“…Mouse and rabbit spermatozoa become more fertile after the addition of a low molecular mass factor from human seminal plasma (Gaur andTalwar, 1973, 1975). Seminal vesicles, augment fertility in rats (Curry and Atherton, 1990).…”

Deregulation of a Hox Protein Regulatory Network Spanning Prostate Cancer Initiation and Progression

“…In contrast to over 2 million U.S. cases of prostate cancer diagnosed in the past decade, there are fewer than 50 cases of primary seminal vesicle cancer in the English literature (3, 4). Similar to the prostate, the development and maintenance of the seminal vesicles is androgen-dependent, and the seminal vesicles synthesize and secrete molecules and proteins that contribute to semen (5). This implies that there are unique differences between prostate and seminal vesicle tissues, which strongly predispose prostate tissue to neoplasia and cancer.…”

Effects of Accessory Sex Gland Fluid on Viability, Capacitation, and the Acrosome Reaction of Cauda Epididymal Bull Spermatozoa

“…For example, in rodents, seminal vesicle secretions may be important to fertility. There was a drastic decrease in the fertility of rodent spermatozoa after seminal vesicle ablation (Curry and Atherton, 1990). This provides evidence that AGF is required for successful in vivo fertilization in rodents; this may be due in part to the semen-coagulating products of the seminal vesicles.…”