Search results for "TESTO"
showing 10 items of 611 documents
Endurance Exercise and Conjugated Linoleic Acid (CLA) Supplementation Up-Regulate CYP17A1 and Stimulate Testosterone Biosynthesis
2013
A new role for fat supplements, in particular conjugated linoleic acid (CLA), has been delineated in steroidogenesis, although the underlying molecular mechanisms have not yet been elucidated. The aims of the present study were to identify the pathway stimulated by CLA supplementation using a cell culture model and to determine whether this same pathway is also stimulated in vivo by CLA supplementation associated with exercise. In vitro, Leydig tumour rat cells (R2C) supplemented with different concentrations of CLA exhibited increasing testosterone biosynthesis accompanied by increasing levels of CYP17A1 mRNA and protein. In vivo, trained mice showed an increase in free plasma testosterone…
The Effects of Chlorotrianisene (Tace) on Kinetics of 3H-testosterone Metabolism in Patients with Carcinoma of the Prostate
1982
Summary— Alterations in the metabolism of testosterone and plasma levels of testosterone, luteinising hormone (LH), follicle stimulating hormone (FSH), prolactin and oestradiol were studied in 6 patients with newly diagnosed prostatic carcinoma before and during treatment with chlorotrianisene at a daily dosage of 48 mg for 14 days. Parameters of plasma kinetics were determined according to the single injection technique and the 2-compartment model, and the plasma hormones by radioimmunoassay. Chlorotrianisene altered neither plasma levels of testosterone, gonadotrophins, prolactin and oestradiol, nor metabolic clearance rate, production rate and other kinetic parameters of testosterone. Th…
The effects of sex hormones, prolactin, and chorionic gonadotropin on pineal electrical activity in guinea pigs.
1981
Microelectrophoretic application of sex hormones onto pineal cells in guinea pigs has shown different responses in pregnant females as compared to males. In pregnant females estrone caused excitation in 74% of the cells tested, while progesterone and testosterone, prolactin, and HCG were inhibitory in a majority of the cells tested, while progesterone and testosterone, prolactin, and HCG were inhibitory in a majority of the cells. In contrast, in males estrone caused excitation of only 19% but inhibition of 37%. A smaller percentage of cells was inhibited by progesterone, while the predominant response to testosterone was excitation. These results suggest that the pineal gland may be under …
Testosterone metabolism in patients with advanced carcinoma of the prostate: a comparative in vivo study of the effects of oestrogen and antiprolacti…
1978
In the light of the high incidence of cardiovascular side effects with oestrogen therapy in patients with prostatic cancer, other medications altering androgen metabolism are under investigation. The influence of the anti-prolactin bromocriptine (CB154) on plasma kinetics of testosterone and on endogenous hormones was studied and compared with the effect of ethinyl oestradiol in 25 patients with prostatic carcinoma. Bromocriptine significantly suppressed both prolactin and testosterone, inhibited the transfer of androgen from the inner pool into the deep compartment and favoured its degradation. Ethinyl oestradiol decreased testosterone, LH and FSH, and prolonged the biological half-life of…
17beta-hydroxysteroid dehydrogenase-3 deficiency: a rare endocrine cause of male-to-female sex reversal.
2006
Deficiency of 17beta-hydroxysteroid dehydrogenase type 3 (17beta-HSD3), due to mutations in the gene encoding the enzyme, results in a rare autosomal recessive form of male-to-female sex reversal. Mutated genes encode an abnormal enzyme with absent or reduced ability to convert Delta4-androstenedione to testosterone in the testis. Affected individuals are genetically males who developed internal male Wolffian structures but female external genitalia. Such individuals are usually raised as females and diagnosis is made at puberty, when they show virilization. Correct diagnosis is mandatory to optimize treatment and follow-up. In the present paper we report the clinical history, endocrine eva…
Effects of Added Resistance Training on Physical Fitness, Body Composition, and Serum Hormone Concentrations During Eight Weeks of Special Military T…
2015
A high volume of military training has been shown to compromise muscle strength development. We examined effects of added low-volume resistance training during special military training (ST) period, which took place after basic training period. Male conscripts (n = 25) were assigned to standardized ST with added resistance training group (TG, n = 13) and group with standardized ST only (control) (CG, n = 12). Standardized ST with added resistance training group performed 2 resistance training sessions per week for 8 weeks: hypertrophic strength (weeks 1-3), maximal strength (weeks 4-6) and power training (weeks 7-8). Maximal strength tests, load carriage performance (3.2 km, 27 kg), and hor…
Relationships between muscle fibre characteristics and physical performance capacity in trained athletic boys
1991
The relationships between muscle fibre characteristics and the physical performance capacity of trained athletic boys (aged 11-13 years) were studied over 2 days. The subjects were divided into two groups according to muscle fibre distribution. The 'fast' group (FG) comprised 10 subjects (sprinters, weightlifters, tennis players) with more than 50% fast-twitch fibres (type II), and the 'slow' group (SG) comprised 8 subjects (endurance runners, tennis players, one weightlifter) with more than 50% slow-twitch fibres (type I) in their vastus lateralis muscle. The 'fast' group had 59.2 +/- 6.3% and the 'slow' group had 39.4 +/- 9.8% type II fibres. Other clear differences (P less than 0.05-0.01…
Decreased prevalence of left-handedness among females with male co-twins: evidence suggesting prenatal testosterone transfer in humans?
2009
Studies of singletons suggest that right-handed individuals may have higher levels of testosterone than do left-handed individuals. Prenatal testosterone levels are hypothesised to be especially related to handedness formation. In humans, female members from opposite-sex twin pairs may experience elevated level of prenatal exposure to testosterone in their intra-uterine environment shared with a male. We tested for differences in rates of left-handedness/right-handedness in female twins from same-sex and opposite-sex twin pairs. Our sample consisted of 4736 subjects, about 70% of all Finnish twins born in 1983–1987, with information on measured pregnancy and birth related factors. Circulati…
Effects of fluoxetine on behavioral deficits evoked by chronic social stress in rats.
2006
Recently, we described an advanced model of chronic social stress in male rats based on the resident intruder paradigm. In this model, rats subjected to daily social stress for 5 weeks showed behavioral changes resembling anhedonia and motivational deficits in humans. In the present study, male Wistar rats were subjected to 5 weeks of daily social defeat by an aggressive conspecific and concomitant treatment with the antidepressant drug fluoxetine (10 mg/kg) after the first week of stress. Compared with controls, rats exposed to chronic stress had significantly reduced locomotor and exploratory activity (rearing and sniffing) and diminished preference for sucrose solution. These effects wer…
Androgen metabolism and biotransformation in nontumoral and malignant human liver tissues and cells
2009
There is indirect multiple evidence that hints at a potential role of sex steroids in development and progression of human hepatocellular carcinoma (HCC). In the present study, we have investigated androgen metabolism in a panel of human liver cancer cell lines (HA22T, Huh7, HepG2) and in normal, cirrhotic and malignant human liver tissues aiming to dissect the potential impact of individual enzyme activities and their products in normal and diseased human liver, both in vivo and in vitro. Using our intact cell analysis we were able to assess rates and pathways of androgen metabolism in living conditions. Overall, incubation of cultured cells or tissue minces with either testosterone (T) or…