On the presence and role of inositol and certain other substances in the seminal vesicle secretion of the boar

Abstract

meso-Inositol was identified as a major chemical constituent of the seminal vesicle secretion in the boar, and isolated in pure crystalline state. The concentration of inositol in the vesicular secretion exceeds considerably the amounts hitherto recorded for material of either plant or animal origin. The fluid secreted by boar seminal vesicles contains 2 to 3 g inositol in 100 ml. The dry matter of the fluid is about 15 g/100 ml., one-third of which is dialyzable; of this between 40 and 70% is composed of inositol. Two methods are described by means of which it is possible to obtain several grams of pure crystalline inositol from the seminal vesicle secretion of a single animal. Certain other characteristic features of the boar vesicular secretion are described, including the occurrence of substances such as fructose as well as an hitherto unidentified carbohydrate, also of ergothioneine and potassium citrate; and an almost complete absence of sodium chloride. One of the functions of inositol and citrate appears to be the maintenance of the osmotic pressure in the seminal vesicle secretion, and probably also in the semen of the boar. The secretion of inositol, ergothioneine, fructose and citric acid, by the seminal vesicles, sets in at an early stage of the development of the boar, a considerable time before the maturation of spermatozoa.