Evaluation of the Functional State of Male Accessory Glands by the Analysis of Seminal Plasma*

Abstract

When one considers the secretory function of the male accessory organs of reproduction, it is important to bear in mind that some of these glandular structures, which may be regarded by morphologists as 'homologous' on the grounds of anatomical or topographical similarity, are by no means homologous in respect of their biochemical and functional characteristics. This situation is particularly true in respect of the seminal vesicle and the prostate. As a result of extensive studies it is now possible to characterize chemically the secretions produced by the seminal vesicle and the prostate, and also those of the epididymis and the Cowper's gland, in many mammalian species, including man. One can also evaluate the functional state of these organs by the chemical analysis of the individual secretions or of the whole seminal plasma. Detailed information pertaining to the question of assessing the secretory function of male accessory organs has been summarized recently (Mann -1971(Mann - , 1974a(Mann - , b, 1975. The examples given below have been selected so as to illustrate how biochemical findings obtained with either the male accessory fluids or the seminal plasma can help t o solve certain specific problems in the physiology and pathology of the male reproductive function.In man, the seminal vesicle, together with the ampulla, constitutes the main source of seminal fructose (Mann -1946(Mann - , 1964. Consequently, the chemical determination of fructose in human seminal plasma serves as a reliable and at the same time quantitative measure of the contribution made by the seminal vesicle and the ampulla towards the whole ejaculate. Among other chemical constituents of the human ejaculate is the exceedingly high content of prostaglandins. These too, are probably derived from the seminal vesicles, but precise information about the origin of all the seminal prostaglandins, now numbering at least 15, is still lacking. This applies particularly to the two recently described 19-hydroxyprostaglandins which occur in the human semen at a concentration of nearly 1Omg/lOOml (Taylor and Kelly -1974).Since the human seminal vesicle and ampulla open jointly into the urethra via the ductus ejuculutorius, one can understand why as a consequence of bilateral occlusion or absence of the ejaculatory ducts, the human ejaculate becomes in such a case not only sperm-free, but fructose-free as well. This fact is nowadays routinely utilized for diagnostic purposes, particularly in congenital bilateral absence of large parts of the excurrent ducts. Needless to say, vasectomy has a different effect: it does not interfere with the function of either the seminal vesicle or the ampulla, and therefore is does not lead to the disappearance of fructose in the seminal plasma. However, in common with patients in whom the vasa deferentia are missing, a vasectomized man would be expected 238 Th. MANN and C. LUTWAK-MANN to yield an ejaculate which is not only sperm-free, but at the same time contains little glycerylphosphorylcholine, since normally thi...

Control of sperm motility and fertility: Diverse factors and common mechanisms

“…In almost all mammalian species, the seminal plasma is considered as one of the main sources of the factors mediating capacitation. Seminal vesicle fluid is the major component of seminal plasma and contains many factors: the activators of sperm motility; fructose and citric acid, which act as the main energy sources of the spermatozoa; prostaglandins that suppress the female immune response; and a semen-coagulating factor that saves sperm metabolism [45][46][47][48][49]. Peitz and OldsClarke reported that the removal of the seminal vesicle in the house mouse decreased the pregnancy ratio and delayed the time of birth [50].…”

Identification of fatty acids in canine seminal plasma

“…Seminal plasma is a complex fluid that is formed mainly by organic and inorganic compounds, such as amino acids, fatty acids, ions, carbohydrates, organic salts and proteins (Mann & Lutwak-Mann, 1976), some of which play a role in regulating sperm function (Strze_ zek et al, 2005). It is known that seminal plasma is important in maintaining sperm motility and viability (Graham, 1994;Maxwell et al, 1997) and increases the resistance of canine sperm to the damage caused by 'cold shock' (N€ othling et al, 2005).…”

Sorbitol dehydrogenase expression is regulated by androgens in the human prostate

“…In the reproductive tract, SORD is believed to be involved in energy production for spermatozoa, due to the high glucose and fructose content in semen (14). Seminal vesicles and ampuls of vas deferences are the main sources of fructose in semen (15). SORD is widely expressed in human tissues (3) and therefore it may have other tissue-specific functions besides converting sorbitol to fructose, as fructose production may not be required in every tissue in which SORD is expressed.…”