M. Sagiv

Sialic Acid Content of Human Spermatozoa and Seminal Plasma in Relation to Sperm Counts

Sialic acid levels were determined in spermatozoa and seminal plasma of 47 semen samples divided into two groups according to sperm counts. Group 1, up to 40 x 10(6) sperm/ml seminal fluid and group 2, above 40 x 10(6) sperm/ml seminal fluid. The content of sialic acid in spermatozoa ranged from 4.4-28.1 micrograms/10(8) spermatozoa and from 70-95 mg/100 ml seminal plasma. Sialic acid was significantly higher in sperm and lower in seminal plasma of group 1 as compared to group 2. The lower content of sialic acid in seminal plasma might have a deteriorating effect on structural integrity of sperm.

Some Properties of Acid and Alkaline Phosphatase in Seminal Fluid and Isolated Sperm

Activities of acid and alkaline phosphatases were examined in spermatozoa isolated from 177 semen samples differing in sperm counts. Alkaline phosphatase was also determined in seminal fluid. The enzymes were assayed using disodium p-nitrophenyl phosphate as substrate and were studied with respect to susceptibility to various concentrations of tartrate (acid) and to heat (alkaline). Electrophoretic separation of alkaline phosphatase from seminal fluid was performed using an Helena apparatus. The results showed that acid phosphatase activity in spermatozoa decreased with increase in sperm densities and that elevation of tartrate from 0.028 to 0.17 M usually correlated an inhibition of the enzyme from 72% to 78% (mean values). Alkaline phosphatase was very low in sperm and generally below the sensitivity of the method used. Activity of alkaline phosphatase in seminal fluid showed a tendency to increase with the increase in sperm counts, but the significance of differences between groups was not statistically valid. Exposure of seminal fluid to 55 degrees C for 16 min resulted in enzyme inactivation of about 90% and in this respect the alkaline phosphatase resembles the enzyme of bone origin. The electrophoretic pattern, however, did not confirm this view and the type of alkaline phosphatase in seminal fluid is not clear.

Andrological Parameters in Men With High Sperm Counts and Possible Correlation With Age

Two hundred eighty six human semen samples with sperm counts above 200 million/ml, were divided into 3 groups according to semen volume: (1) less than 1 ml (low), (2) 1 ml-5 ml (normal), and (3) greater than or equal to 6 ml (high). Each group was examined for routine andrological parameters. Also examined was a possible correlation between sperm counts, semen volumes, and ages of patients. The quality of motility (percent and grade) and viability of sperm were generally lowest in specimens with a volume below 1 ml and highest in those of normal volume. Proportions of morphological normality exhibited a similar trend, lacking, however, statistical significance. The mean fructose content of low-volume semen was significantly decreased in comparison with those of normal volume. Patients with low-volume semen and sperm counts above 200 million/ml were older than those with similar sperm counts and normal volume. The mean ages of all patients with high sperm counts of semen were higher than of those with lower sperm counts. It was assumed that in contradiction to specimens with high sperm counts and low volume, those whose volumes range from 1 ml-5 ml should be considered normal with respect to motility, viability, and morphological normality.

β-Endorphin and calcitonin in human semen

The levels of β-endorphin (β-E) and calcitonin were estimated in 36 samples of seminal plasma from semen of normospermic, oligozoospermic, and azoospermic origins and in pools of isolated sperm. The mean levels in plasma calculated for all samples examined were 192. ± 224 pg/ml for β-E and 754 ± 397 pg/ml for calcitonin. The amounts in sperm were as follows: for β-E in pols with sperm counts of 0.1–10 × 106/ml, 157.2 ± 99.7 pg/108 and 27.9 ± 23.6 pg/ml protein; in pols of > 10–30 × 106/ml, 71.2 ± 41.5 pg/108 and 6.5 ± 1.2 pg/mg protein; in pools of > 30–200 × 106/ml, 24.9 ± 9.7 pg/108 and 61 ± 1.9 pg/mg protein. For calcitonin the amounts were: 501.2 ± 170.8 pg/108 and 27.4 ± 21.5 pg/mg protein, correspondingly. It was suggested that β-E and calcitonin present in seminal plasma are synthesized mostly in a compartment of the male reproductive system. The high cellular β-E and calcitonin levels would be involved in the process of motility through their effect on calcium transport.

β-endorphin in normozoospermic and pathologic human semen

β-Endorphin was estimated in normozoospermic, oligozoospermic and azoospermic human semen. The mean amount in normozoospermic specimens was 278.6±43.6 (SE) pg/ml while in the others only 191.1±25 pg/ml. Both values are significantly higher than those present in the blood.

ATP contents of human semen, seminal plasma and isolated sperm at time intervals after ejaculation

1. ATP was estimated in 105 samples of human semen, seminal plasma and sperm of normozoospermic and oligozoospermic origins at time intervals after ejaculation. 2. In semen with sperm counts up to 40 millions per ml and in seminal plasma, ATP levels were lower than in specimens with higher sperm counts. 3. In isolated sperm, the ATP content decreased with the increase in sperm density. 4. The decrease in ATP after 24 hr was the highest in sperm, lower in semen and the lowest in seminal plasma, being maximal in specimens with high sperm counts.

Vitamin A and β-Carotene Content of Seminal Fluid and Sperm of Normospermic and Oligozoospermic Men

Beta-carotene and vitamin A were estimated in 125 specimens of human seminal fluid and spermatozoa. In 72 of the specimens triiodothyronine, tetraiodothyronine, and T4-binding globulin were also determined. Vitamin A in seminal fluid increased from 10.4+/-l.8 microgram (SE) in severe oligozoospermia up to 19.1+/-2.5 microgram/100ml in specimens with high sperm densities. In spermatozoa, however, there was a trend for a decrease in vitamin content from 2.1+/-0.8 to 0.2 +/-0.07 microgram/108. In the majority of cases beta-carotene was undetectable and, when present, the levels were much lower than those of vitamin A. The amounts of triiodothyronine and tetraiodothyronine in seminal fluid were 0.19+/-0.03 ng/ml and 1.1+/-0.18 microgram/100ml, respectively. No correlation was found between levels of both hormones and quality of seminal fluid. T4-binding globulin was either very low or undetectable.

Motility and vitality of human spermatozoa at various time intervals after ejaculation

Motility and vitality of spermatozoa from semen differing in sperm density were assessed at various intervals after ejaculation. Percentile decreases in both parameters were found to be higher in oligospermic specimens than in those with higher sperm densities.

Acid Phosphatase Activity in Human Semen

Acid phosphatase activity was examined in normal and abnormal human semen of individuals not suffering from testosterone deficiency. No differences in enzymatic activity between the examined groups were observed. The presence of tartaric acid caused an inhibition of about 95% of enzymatic activity.

Distribution of Sialic Acid in Human Sperm Membranes

Sialic acid was estimated both chemically in populations of heads and tails of spermatozoa from normospermic human seminal fluid and by transmission electron microscopy, using a specific labeling technique. The results of both procedures show that sialic acid is located exclusively in the head plasma membrane and in the acrosomal membranes. It is suggested that localization of sialic acid close to that reported for neuraminidase in sperm might be of importance in the fertilization process.