Alterations of lipid metabolism in men with hypotestosteronemia.

Studied relationship in serum concentration of testosterone and lipids in 35 men with a positive coronarographic finding and 30 sterile men, in comparison with a control group. From lipid parameters we determined serum concentration of cholesterol, triacylglycerols and apolipoprotein B, and lipid distribution in lipoprotein fractions. Serum testosterone concentration was found decreased in both the group as against the controls. As to lipid parameters, cholesterol concentration was depressed in the high-density lipoprotein (HDL) fraction of both the clinical groups. As increased apolipoprotein B level was seen in men with the positive coronarographic finding. The results point to a negative effect of lowered testosterone concentrations on lipid metabolism.

Lipid metabolism in young males with hypotestosteronaemia and oligospermia prior to, during, and after treatment.

Relationships between plasma testosterone levels and selected parameters of lipid metabolism were studied in a group of young sterile males prior to, during, and after hormone therapy. Initial hypertriacylglycerolaemia and decreased concentrations of HDL cholesterol returned to normal values after 30 days of methyltestosterone administration. LDL cholesterol concentrations decreased significantly as did plasma apolipoprotein B levels. These changes persisted also one month after cessation of treatment. The results suggest that restoration of initially decreased testosterone levels in the studied group of sterile males is associated with the restoration of the lipid profile.

Some measures of lipid metabolism in young sterile males before and after testosterone treatment.

The concentration of total cholesterol and triacylglycerols in plasma and their distribution in lipoproteins as well as the level of apolipoprotein-B and of endogenous testosterone were measured in 30 young sterile males before and after the treatment with methyltestosterone (Agovirin SPOFA) in a dose of 10 mg daily for 30 days. Before the treatment the level of total cholesterol in plasma and in VLDL fraction was normal, while that in LDL fraction was increased and in HDL fraction decreased. Similarly, the level of triacylglycerols in plasma was increased and correspondingly also the levels of that in all lipoprotein fractions. After the treatment no changes in total and VLDL cholesterol were found, while a significant decrease in LDL fraction and increase in HDL fraction was observed. Moreover, a significant decrease was found in a level of total plasma and VLDL triacylglycerols.

The influence of various aetiopathogenetic factors on testicular function.

Three hundred and seventy-one patients with azoospermia were examined by means of testicular biopsy. The patients were assigned to seven histological groups according to the degree of damage found in their germinative epithelium. The degree of damage to the germinative epithelium was correlated with the aetiopathogenetic factors.

Effect of short-term androgen administration to rabbit females on their lipoprotein metabolism.

The changes of lipoprotein profile were studied in rabbit females administered 1 mg/kg testosterone propionate i.m. daily for 7 days. Under such conditions a decrease of cholesterol in serum and in LDL fraction was found together with the increase of that in VLDL fraction. The level of triacylglycerols was decreased in serum, in VLDL and HDL fractions. These results showed that even a short-term administration or testosterone in pharmacological doses resulted not only in a decrease of total cholesterol in serum, but also influenced favourably its level in LDL fraction.

Effect of short-term estrogen administration on some parameters of lipoprotein metabolism in male rabbits.

A follow-up of short-term administration of estrogens on certain parameters of the lipid metabolism in male rabbits has revealed significant changes in the distribution pattern of their cholesterol in the LDL (decline from 0.5 +/- 0.05 to 0.25 +/- 0.04 mmol l-1) and in the HDL fraction (increase from 0.22 +/- 0.02 to 0.5 +/- 0.02 mmol l-1), as also a striking increase of serum triglycerides (from 0.85 +/- 0.1 to 1.52 +/- 0.12 mmol l-1) and of triglyceride concentration in the VLDL lipoprotein fraction (from 0.09 +/- 0.06 to 0.65 +/- 0.11 mmol l-1) (P less than 0.05). The changes in the remaining indicators are not significant. The results obtained make it clear that even a short-term administration of estrogens significantly affects the lipoprotein profile in male rabbits, making it similar to that of females.

Concentration of lipid, apoprotein-B and testosterone in patients with coronarographic findings.

The relationship between lipid, apolipoprotein-B and testosterone concentration and indicated coronarography was followed in male patients assigned into two age groups (under and over 50 years). Patients without a positive finding on coronary vessels served as controls. Patients of both age groups with a positive coronarographic finding showed an enhanced apolipoprotein-B and a decreased cholesterol concentration in the HDL2-high density lipoprotein subfraction. Likewise, testosterone level was also decreased in the two age groups. It appears that a lowered testosterone level may indirectly intervene into lipoprotein metabolism, or may affect the apolipoprotein-B level.

Intersex differences in plasma lipid content and in various lipoprotein fractions in New Zealand albino rabbits.

Total lipids in plasma were determined and also the content of cholesterol, triglycerides, phospholipids and proteins were assayed in various lipoprotein fractions (VLDL, LDL, HDL) isolated by means of preparative ultracentrifugation, in rabbits of both sexes of the New Zealand albino strain. Significant intersex differences were noted in total plasma lipids as also in the cholesterol, triglyceride and phospholipid content in all the lipoprotein fractions. These parameters proved to be significantly higher in females than in males. Cholesterol content was higher in the fraction of low density lipoproteins (LDL) and lower in that of high density lipoproteins (HDL) in the males. As to females, cholesterol was uniformly distributed in both the LDL and HDL fractions. Determination of the representation of the various apoproteins with the aid of gel electrophoresis failed to yield any intersex differences.

Testosterone concentration in plasma and its production in the testes of the rat following testosterone, oestradiol and HCG application.

The authors present data on the effect of a seven-day application of testosterone, oestradiol and HCG to male rats, on plasma concentration and testicular production of testosterone. In addition, they also studied the in vitro effect of LH on testosterone production in control male rats and rats treated with testosterone, oestradiol and HCG. Plasma testosterone concentration was higher in animals treated with testosterone and HCG (exogenous effect) than in the control group. Oestradiol-treated males had a markedly lowered plasma concentration of testosterone. A striking decline in testosterone production was noted in the testes of male rats receiving testosterone and oestradiol in comparison with the controls. Testosterone production failed to increase even after LH had been added to the incubation medium. A maximum testosterone production in the testes was achieved following HCG application. Testosterone concentration in plasma and in incubates was determined by radioimmunoassay. On the basis of the results, the authors suggest the significance of sex hormones and their effect on the mechanisms controlling testosterone production in the testicular gland. Control of testosterone production takes place not solely in the hypothalamo-hypophyseal system, but to a great extent also at the cellular level of the sex gland itself.

Endogenous production of ovarian estradiol-17 beta and its plasms levels in young rats.

Estradiol-17 beta concentration in the plasma and its production in ovaries of Wistar rats have been assayed from infancy until puberty (i.e. from the 5th till 39th days of postnatal life). The highestest estradiol-17 beta plasma concentration was found between the 15th and 20the postnatal day. 24 hrs before the vagina opened plasma estradiol-17 beta rapidly rose. Estradiol-17 beta reproduction between days 15 and 33 remained at a stable level, but its production was highest at 39 days. The increase in estradiol-17 beta production and its plasma concentration on the 35th postnatal day until the immediate onset of puberty points to a maturation process occurring at a certain period in the development of sex function in which estrogens plays a dominant role.

Postnatal development of gonadotropin binding sites and cAMP synthesis in ovaries and estradiol plasma levels in estrogenized or androgenized female rats.

The binding of 125I-HCG by ovarian homogenates was studied in adolescent rats injected with 100 microgram estradiol dipropionate or 50 microgram testosterone propionate at the age of three days. Estrogenized and androgenized female rats showed a decrease of gonadotropin binding in ovaries at the 25th postnatal day. After the day 40, however, there was an increase in gonadotropin binding capacity above that in control animals. The changes of specific binding of 125I-HCG by ovaries of rats neonatally treated with sex hormones did not correlate with either the responsiveness of cAMP synthesis in ovaries to LH or with plasma levels of estradiol-17beta in postnatal development.

Correlation of ovarian binding of 125I-HCG with formation of cAMP, estradiol and progesterone during pregnancy.

The content of ovarian gonadotropin receptors in rat was found to change during pregnancy. The specific binding of 125I-HCG to ovarian homogenates rose to its maximal values on days 13 and 16. Thereafter, the binding declined as parturition approached. No consistent changes in responsiveness of rat ovary to LH in synthesis of cAMP and estradiol were observed during pregnancy. Plasma estradiol concentration increased on day 16 and remained high throught days 21 and 22. Progesterone levels increase steadily during the first half of pregnancy and then fall, especially sharply on day 21 and 22. The results demonstrate that the secretion of progesterone correlates with gonadotropin receptors during pregnancy.

Production of oestradiol, camp and 125I-hcg binding by rat ovaries during the reproductive cycle.

Plasma concentration of oestradiol in female rats is dynamically altered in the reproductive cycle, depending on the biosynthesis and secretion of oestradiol secretion by the ovaries. The present study has followed oestradiol and cAMP concentration in the plasma and ovaries, and 125I-HCG binding during the pro-oestrus, oestrus and di-oestrus. Oestradiol concentration in plasma and its production by the ovaries were found to be highest in the pro-oestrus and lowest in the oestrus. These changes depend on the production and secretion of gonadotrophins. The mediator of gonadotropin action is cAMP whose ovarian concentration is lowest in the oestrus. LH stimulates the cAMP synthesis in the ovaries during the cyclic stages, without any significant difference being apparent between the various stages. 125I-HCG binding is highest in the di-oestrus stage, when concentration of endogenous gonadotrophins is low.