Androgen effects

The mechanism by which TBT causes these effects has been extensively stiidied. The androgenic effects of TBT appear to be caused by interference with steroid biosynthesis rather than by mimicking the action of testosterone at the androgen receptor. Exposure of female molluscs to TBT leads to an elevation in testosterone in the haemolymph. " Much of the experimental evidence... 

A randomized, double-blind, placebo-controlled trial evaluating the use of a monophasic OC containing 30 meg ethinyl estradiol and 3 mg drospirenone, a progesterone with anti-androgenic effects, showed improvement in the treatment arm compared with placebo.31 In particular, appetite, food cravings, and acne improved. However, active treatment was not associated with a statistically significant improvement in the overall outcome measure, the Calendar of Premenstrual Experiences (COPE) scale, perhaps because of the small sample size (n = 82). 

Yamada T, Ueda S, Yoshioka K et al (2003) Lack of estrogenic or (anti-)androgenic effects of d-phenothrin in the uterotropic and Hershberger assays. Toxicology 186 227-239... 

The explanation for this phenomenon is that in the prepubertal phase the amount of testosterone that is secreted is not sufficient to cause development of the male genitalia, which is normally stimulated by dihydrotestosterone. However, at puberty the secretion of testosterone increases. The increase is large in this syndrome, because lack of dihydrotestosterone decreases the extent of the feedback inhibition of the hormone secretions by the pituitary so that more gonadotrophins are released which stimulate, markedly, the rate of testosterone secretion and hence its concentration in the blood. At these high levels, testosterone has sufficient androgenic effects to stimulate development of the external genitalia. 

Newly proposed test guidelines to specifically address effects on hormone homeostasis and on male and female reproductive organs include the rodent uterotrophic assay to detect estrogenic effects (OECD 2007a) and the rodent Hershberger assay to detect androgenic effects (OECD 2007b). 

Androgenic effects Androgenic effects may not be reversible even when the drug is discontinued. Watch patients closely for signs of virilization. 

D. The enzyme 5a-reductase catalyzes the formation of dihydrotestosterone from testosterone. In normal accessory sex gland tissues, such as the prostate, most of the direct androgen effect is due to dihydrotestosterone rather than testosterone. Thus when 5a-reductase is lacking, serum levels of testosterone may be normal or even slightly elevated with a hypotrophied prostate gland. 

Anti-anaphylactic activity. Water extract of the dried fruit, at a concentration of 1 pg/ mL, produced weak activity on the rat Leuk-RBL 2H3 vs biotinyl immunoglobulin E-avidin complex-induced degranulation of (3-hexosaminidase 5 Anti-androgenic effect. Ethanol (95%) extract of the aerial parts, administered intraperitoneally to castrated mice at a dose of 2 mg/animal, produced strong activity The dried leaf, smoked by 13 male adults for 21 days, was inactive . 

Anti-androgenic effect. Sterol fraction of the dried fruit, in cell culture, was active on CA-PC3 and reduced androgen-induced reporter gene expression in transcriptional assay IC50 50 pg/mL . Administration to... 

Elocalcitol (BXL-628) is the fluoro analogue of the D3 metabolite that inhibits the growth factors involved in benign prostatic hyperplasia (BPH) it is without direct androgenic effects and does not cause hypercalcemia. It is in Phase 11 development for the treatment of BPH and overactive bladder (cf. Chapter 4). " ... 

There are no firm data on the use of corticotropin in pregnancy both glucocorticoid and androgenic effects might be expected to affect the fetus. 

It is doubtful whether one can avoid unwanted androgenic effects by cautious dosing. For example, the... 

Roxithromycin may have anti-androgenic effects. In an in vitro model roxithromycin 5 pg/ml suppressed androgen receptor transcriptional activity by 21% (1050). 

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