742 



SPERM, OVA, AND PREGNANCY 



TABLE 13.9 



Composition of bovine genital fluids 



(From N. L. VanDemark, Internat. J. Fertil., 3, 



220-230, 1958.) 



Dry matter (per cent) 



Ash (percentage of dry matter) 



Sodium (mg. per 100 ml.) 



Potassium (mg. per 100 ml.) 



Calcium (mg. per 100 ml.) 



Total N (gm. per 100 ml.) 



Reducing substance (as mg. glucose 

 per 100 ml.) 



7.5 

 9.3 

 304 

 36 

 12 

 0.96 



contributed extensive data concerning the 

 chemical composition of the uterine fluids of 

 the rabbit, rat, and dog (Table 13.10). 



An interesting report on potassium and 

 sodium concentrations of uterine fluid in the 

 proestrous rat indicates that K is relatively 

 high (37 niEci./l.) and remains constant 

 after copulation with a vasectomized male; 

 Na decreases, however, by about 11 per 

 cent from the initial value of 115 niEq./l. 

 (Howard and DeFeo, 1959). The shift may 

 be due to the change from follicular to 

 luteal phase, but because of the contribu- 

 tions of the several accessory glands, the 

 significance of the change is not clear. None- 

 theless, the high initial K/Na ratio (0.32) 

 suggests a marked K-tolerance on the part 

 of the spemi and, further, a secretory action 

 of the genital mucosa leading to the ac- 

 cumulation of potassium within the lumen. 



The paucity of data concerning enzymatic 

 activity by the uterine fluids was indicated 

 by Reynolds (1949). Since that time little 

 has been added, except for two suggestive 

 papers dealing with amylase activity of the 

 tube and its fluids. Human tubal cysts con- 



tain high concentrations of such an enzyme 

 and have led to the supposition that intra- 

 luminal glycogen — if any should exist — 

 might be hydrolyzed to provide a substrate 

 for sperm (Green, 1957). McGeachin, Har- 

 gan, Potter and Daus (1958) confirmed 

 the presence of amylase in the cysts and 

 found high activities also in tubal epi- 

 thelium of man, rabbit, cow, and sheep, but 

 not of other species studied. In an elec- 

 trophoretic study of the cornual fluids of 

 the estrous rat, low concentrations of 4 ma- 

 jor proteid components were found, which 

 appeared to differ in their mobility charac- 

 teristics from serum proteins (Junge and 

 Blandau, 1958). 



It is clear that energy substrates and 

 other biochemical components of seminal 

 plasma are introduced into the tubes in 

 animals in which intrauterine ejaculation 

 occurs (Mann, Polge and Rowson, 1955). 

 However, the significance of these constit- 

 uents for tubal i)hysiology is highly doubt- 

 ful after intravaginal insemination. Rela- 

 tively little glycolytic substrate seems to be 

 present in the fluids recovered from the 

 tract. In the rabbit, for example, little or no 

 hexose, and only traces of phospholipids, 

 can be detected, either before or after 

 cojmlation (Table 13.11) ; lactate is present 

 in appreciable quantities and might con- 

 ceivably serve as a metabolic substrate 

 (Bishop, 1957; Mastroianni, Winternitz 

 and Lowi, 1958). At the present time, it is 

 not easy to ascertain which metabolic sub- 

 strates and products are associated with the 

 activities of the spermatozoa and which 

 with the activities of the mucosal cells lin- 

 ing the tract. More work is necessary to fill 

 in the metabolic and physiologic details of 

 the sketch just barely outlined. 



Abundant evidence indicates that the 

 tubal contents are a product of active se- 



TABLE 13.10 



Chemical composition of uterine fluids 



(From H. E. Shih, J. Kennedy and C. Huggins, Am. J. Physiol., 130, 287-291, 1940.) 



