A comparison of various parameters of prostatic and vesicular secretory function was made between the seminal plasma of young (20-25 years; n = 23) and middle-aged (50-55 years; n = 19) male volunteers. These parameters included prostatic acid phosphatase, zinc, citric acid, spermine, spermidine, putrescine (prostatic origin), fructose, and prostaglandin E (vesicular origin), in addition to protein and testosterone. Spermatozoa were counted and monitored for abnormalities. The concentration in the ejaculate of the majority of the parameters investigated did not change with age, although the total contribution to the ejaculate from the prostate and seminal vesicles was reduced significantly in the older men. The concentration of three constituents was significantly altered in the older age group: putrescine (P less than 0.001) and prostaglandin E (P less than 0.01) were reduced, while zinc levels were elevated (P less than 0.05). These changes are discussed in relation to possible disturbances of prostate function and pathology in the middle-aged man.

Acid Phosphatase↗

PubMedDate not supplied

Biphasic effect of testosterone propionate on Sertoli cell secretory function.

When various doses of testosterone propionate (10 to 10,000 mug/day) were given to 21-day-old rats for 10 days a biphasic effect was seen both on testis weight and production of androgen-binding protein (ABP). At low doses (10 to 100 mug testosterone propionate/day) there was a reduction in testis weight as well as ABP content in the epididymis. At higher doses of testosterone propionate, there was a stimulation of both testicular weight and ABP production in spite of suppressed serum FSH and LH levels. These effects of testosterone propionate on Sertoli cell secretory function strongly suggest that the Sertoli cell is a target cell for androgen.

Animals↗

PubMedDate not supplied

Effects of oestrogen-induced hyperprolactinemia on the rat prostate.

Exposure of intact rats to increasing doses of oestradiol-17 beta in the presence of a constant amount of exogenous androgen caused a dose-related increase in the concentration of zinc in the lateral lobes and a decrease in the levels of ventral lobe prolactin binding. These changes occurred concomitantly with a dose-dependent increase in plasma prolactin levels, and could not be obtained in hypophysectomized rats given the same steroid treatment. In the intact animals a dose-dependent decrease in the responsiveness of the prostaglandin E1-dependent adenylyl cyclase in the ventral lobe was observed, an effect which has earlier been shown to be prolactin mediated. The results indicate that oestrogen has indirect effects on specific parameters of prostate function by inducing a relative hyperprolactinemia. This model may be useful in studying effects of chronically and physiologically elevated levels of endogenous prolactin on the rat prostate.

Adenylyl Cyclases↗

PubMedDate not supplied

Androgen interaction with the polyamine system of the rat prostate.

The ventral and dorsal lobes of the rat prostate contain larger quantities of the aliphatic amines putrescine, spermidine and spermine and higher activities of the enzyme ornithine decarboxylase (ODC; EC 4.1.1.17) than other accessory sex glands. In contrast, the coagulating glands and the seminal vesicles contain only small quantities of the amines but the highest activities of the arginase (ARG; EC 3.5.3.1). Lineweaver-Burk plots indicated that the Km-values for ARG in the coagulating gland and ODC in the ventral prostate lobe were 20 mM and 0.2 mM, respectively. Castration decreased ODC and ARG activities to 3 and 50% of control levels, respectively, after 3 days, whilst the Km-values were unaffected. Daily administration of 3 mg dihydrotestosterone (DHT) prevented these castrational changes. Oestrogen treatment alone had no effect on the activities of the enzymes, but appeared to exert a synergistic effect with androgen on the ODC. Administration of androgen to intact rats for 7 days caused a dose-related alteration in the ratios of the various amines, particularly the spermine: putrescine ratio. A minor but significant decrease was also recorded in the activity of the ODC, which was mirrored by an increase in the levels of putrescine in the tissue. The data suggest that androgen control of the polyamine pathway is biphasic, first stimulatory and later inhibitory with lesions occurring at the ODC, possibly via short loop feedback of its product putrescine, but also at subsequent enzymic steps in spermidine and spermine biosynthesis.

Animals↗

PubMedDate not supplied

Effects of varying the abstinence period in the same individuals on sperm quality.

Fourteen men each provided semen samples after 3, 6, and 10 days abstinence in a sequence decided by the individual and over a period of approximately 6 weeks. The proportion of sperm displaying progressive motility remained relatively constant up to 6 days but declined after a further 4 days of abstinence. This decrease was not associated with any major changes in sperm morphology or vitality. The total number of sperm with progressive movement in the ejaculate increased after 6 days and remained high after 10 days of abstinence. In subjects with asthenozoospermia, the greatest increase in the total number of sperm in the ejaculate occurred between 6 and 10 days. For men with reduced sperm quality participating in assisted fertilization programs, it may be advantageous to advise longer periods of abstinence, up to 10 days, prior to semen collection.

Humans↗

PubMedDate not supplied

Life styles of men in barren couples and their relationship to sperm quality.

This study is based on a questionnaire which focused on the possible association between life-style factors and male fertility in a group of 252 men attending our laboratory in connection with a fertility investigation. Their answers were correlated to sperm quality. No association could be documented between sperm quality and smoking habits, coffee drinking, a moderate alcohol intake, exposure to heat (sauna, hot baths, type of underwear, sedentary activities), or physical activities in their leisure time. In contrast, the reported average ejaculation frequency was significantly positively correlated to the motility of the sperm (% progressive), and inversely related to the proportion of sperm with abnormal morphology and semen volume. This indicates that the life style of the subject has little if any impact on semen quality, at least within the limits recorded in the present study.

Alcohol Drinking↗

PubMedDate not supplied

Provocation testing of human sperm motility using energy substrates and activators of the cyclic nucleotide system. I. Establishment of conditions for response testing.

In order to establish a series of provocation tests to evaluate the integrity of the sperm cAMP pathway, manganese (Mn), 2-deoxyadenosine (DEA) (via adenylyl cyclase), and methyl-isobutyl-xanthine (MIX) (via phosphodiesterase) were tested for their capacity to activate the progressive motility of human sperm. Optimal responses were obtained using washed sperm previously incubated for 3 hours in substrate-poor medium (Hepes-buffered saline). Longer periods of incubation required the presence in addition of an energy substrate such as glucose. Exposure of sperm to seminal plasma for 24 hours prior to washing attenuated the responsiveness of the sperm to the different activators. Preliminary studies on the activation of the progressive motility of washed sperm from four normozoospermic men under fertility investigation, prepared under identical conditions, revealed differences in the pattern of response which may have pathophysiological relevance.

1-Methyl-3-isobutylxanthine↗

PubMedDate not supplied

Application of flow cytometry to studies on the human acrosome.

This study describes the use of flow cytometry combined with specific labelling of the human sperm acrosome using a FITC-labelled plant lectin (Arachis hypogea agglutinin). Localization of the label to the acrosome was encouraged by freezing the sperm for at least 24 hours at -70 degrees C prior to labelling. Studies of sperm from 53 normospermic men revealed that acrosome labelling followed a single normal distribution without the presence of subpopulations. The average fluorescence and degree of variation within the sperm population differed markedly between sperm samples. These differences could not be predicted by any of the normal criteria of sperm quality, including sperm morphology, vitality, and motility. Exposure of washed sperm to the calcium ionophore A 23187 in the presence of calcium at 37 degrees C, caused a time-related leftward shift in the distribution of acrosome fluorescence, indicating that this technique can be also used to monitor the acrosome reaction.

Acrosome↗