386 



PHYSIOLOGY OF GONADS 



is not synthesized in the animal V)ody (Alel- 

 ville, dtken and Kovalenko, 1955; Heath, 

 Rimington and Mann, 1957). Because 

 orally ingested S'^'"'-labeled ergothioneine 

 l)asses into the seminal plasma of the boar 

 (Heath, Rimington, Glover, ]Mann and 

 Leone, 1953) , it is possible that those acces- 

 sory glands which secrete ergothioneine 

 concentrate this substance from the blood. 



Mann and Leone (1953) are of the opinion 

 that the function of ergothioneine in seminal 

 plasma is to protect the spermatozoa from 

 the poisonous action of oxidizing agents. It 

 is remarkable that the seminal fluids of the 

 boar and the stallion, both of which contain 

 ergothioneine, have common characteristics 

 which would render their spermatozoa es- 

 pecially sensitive to oxidizing agents, viz., 

 large volume, low sperm density, and small 

 content of glycolyzable sugars. 



PoLYAMiNES. Large amounts of spermine 

 and spermidine are present in the prostate 

 gland of many species (Harrison, 1931 ; 

 Rosenthal and Tabor, 1956). The chemical 

 structure of these polyamines was elucidated 

 by Dudley, Rosenheim and Starling (1926, 

 1927). Human seminal plasma contains as 

 much as 300 mg. spermine per 100 ml., most 

 of which is derived from the prostate gland. 

 If human semen is allowed to stand for a 

 few hours at room temperature, the spermine 

 present crystallizes in the form of spermine 

 phosphate ("Boettcher's crystals").- Both 

 spermine and spermidine are oxidized by the 

 diamine oxidase of human seminal plasma 

 (Zellcr, 1941; Zeller and Joel, 1941). These 

 polyamines via their degradation products 

 are highly toxic to spermatozoa (Tabor and 

 Rosenthal, 1956) , and it seems unlikely that 



"In a letter written to llie Royal Society of 

 London in November 1677, Antoni van Leeuwen- 

 hoek described for the fir.'^t time tlie presence and 

 movement of spermatozoa in human semen. In 

 the same letter, he also mentioned that "three- 

 sided bodies," which were "as bright and clear as 

 if they had been crystals," were deposited in the 

 aged semen of man. These crystals were undoubt- 

 edly composed of spermine phosphate. The liis- 

 tory of the discovery of spermine in semen is ad- 

 mirably summarized by Mann (1954a), with special 

 reference to the contributions of Louis Vauquelin 

 (see footnote 3), and also of Alexander von Pcihl, 

 whose claims for the therapeutic proiinities' of 

 spermine aroused much interest aiul controversy 

 at the end of the 19th centurv. 



their presence in seminal plasma is of func- 

 tional value. 



Choline DERIVATIVES. Florence (1895) de- 

 scribed the formation of brown crystals 

 upon the addition of a solution of iodine in 

 potassium iodide to semen. This reaction was 

 used as the basis of a medico-legal test for 

 semen stains. Bocarius (1902) showed that 

 choline was responsible for the formation 

 of this material. In the rat, the seminal 

 fluid is by far the richest source of choline 

 of any tissue or body fluid (Fletscher, Best 

 and Solandt, 1935). A series of careful stud- 

 ies by Kahane (Kahane and Levy, 1936; 

 Kahane, 1937) revealed that human semen 

 contains very little free choline immediately 

 after ejaculation, but that large amounts of 

 the free base are formed if the semen is al- 

 lowed to stand at room temperature. Lund- 

 quist (1946, 1947a, b, 1949) isolated phos- 

 phorylcholine from human seminal plasma 

 and showed that it was converted to choline 

 and inorganic phosphate by seminal acid 

 phosphatase. However, the French investi- 

 gators (Diament, Kahane and Levy, 1952. 

 1953; Diament, 1954) isolated a-glycero- 

 phosphorylcholine from the vesicular secre- 

 tion of rats, and suggested that this sub- 

 stance, rather than phosphorylcholine, was 

 the precursor of free choline in aged semen. 

 Lundquist (1953) also found glycerophos- 

 l^horylcholine in tlie vc'sicular secretion of 

 the rabbit, rat, and guinea pig. Williams- 

 Ashman and Banks (1956) showed that the 

 amount of glycerophosphorylcholine in rat 

 vesicular secretion falls rapidly after castra- 

 tion, and can be restored to normal levels by 

 administration of testosterone. Rezek and 

 Sir (1956) found both ]')hosi)liorylcholinf 

 and glyceroi)hospliofylclu)line in lunnan 

 ejaculates. 



A thorough study of the wat('i'-s()lul)lf 

 choline (lerivati\-cs in seminal plasma was 

 made by Dawson, Maiui and White (1957). 

 They foimd (Tabh'().4i that in most species, 

 gh^cerophosphoryh-holine is the only deriva- 

 ti\'e preseiu, but ill man there are consider- 

 ■a\)\v (|uantities of phosphoiyh'lioline as well. 

 The lattei- substance is rai)idly dephospho- 

 lylated after ejaculation, but glycerophos- 

 phoryh'holine is not degradeil by enzymes 

 in seminal phisnia or \'esiculai' secretion. In 



