Testosterone levels

LH-RH (Luteinizing Hormone-Releasing Hormone) agonists are drugs that inhibit the secretion of sex hormones. In men, LH-RH agonists cause testosterone levels to fall. In women, LH-RH agonists cause the levels of estrogen and other sex hormones to fall. 

This system is designed for application to scrotal skin only (the astern is five times more permeable to scrotal skin). Testoderm or Testoderm Adhesive will not produce adequate serum testosterone levels if applied to other diin sites... 

Pent et al. 1998). Thus, inhibition of P450s other than aromatase might cause elevation of testosterone levels. 

FIGURE 7 Serum testosterone levels in three baboons treated with a single injection of testosterone-loaded microspheres. 

There has been some speculation that estrogenic compounds may adversely affect the fertility of men by reducing testosterone levels and sperm counts (Atanassova et al, 2000). To date, however, the limited information available suggests that consumption of phytoestrogens does not affect reproductive hormones or semen quality (Nagata, 2000 Nagata et al., 2001 Mitchell et... 

SHARPE R M, MARTIN B, MORRIS K, GREIG I, MCKINNELL, MCNEILLY A S, WALKER M (2002) Infant feeding with soy formula mflk effects on the testis and on blood testosterone levels in marmoset monkeys during the period of neonatal testicular activity. Human Reproduction. 17 1692-1703. 

In some animals, consumption of a phytoestrogen-rich diet can cause temporary infertility and reproductive system disorders (Irvine, 1999). In humans, lower testosterone levels and a decline in human semen quality over the past century have been luiked to increased exposure to environmental endocrine disrupters (EDCs) (Sharpe and Skakkebaek, 1993). Furthermore, cases of sexual impotence have been reported in males exposed to synthetic estrogens in the pharmaceutical industry (Mattison et al., 1990). If this might be the case, the fetal-prepubertal period and Sertoli cell development would be of critical importance (Sharpe and Skakkebaek, 1993). However, an adverse effect of phytoestrogens on male fertility has yet to be proven. Recent work (Mitchell et al., 2001) addressing this point led to the conclusion that up to 40 mg/day of isoflavones over a two-month period had no effects on gonadotrophin and... 

Monitor serum DHEA-S (aim for the middle range of normal levels in healthy young people) and free testosterone level. 

Androgens are important for general sexual function and libido, but testosterone supplementation is only effective in patients with documented low serum testosterone levels. 

Androgens are important for general sexual function and libido, but testosterone supplementation is only effective in patients with documented low serum testosterone levels. In patients with hypogonadism, testosterone replacement is the initial treatment of choice, as it corrects decreased libido, fatigue, muscle loss, sleep disturbances, and depressed mood. Improvements in ED may occur, but they should not be expected to occur in all patients.23 The initial trial should be for 3 months. At that time, re-evaluation and the addition of another ED therapy is warranted. Routes of administration include oral, intramuscular, topical patches or gel, and a buccal tablet. 

Androgen ablation = serum testosterone levels less than 50 ng/mL. LHRH agonist (medical castrations or surgical are equivalent). 

Hypogonadism A condition resulting from or characterized by abnormally decreased functional activity of the gonads, with retardation of growth and sexual development or reduced or absent secretion of hormones from the sex glands resulting in low testosterone levels in men. 

C19. Christeff, N., Benassayag, C., Carli-Vielle, C., Carli, A., and Nunez, E. A., Elevated estrogen and reduced testosterone levels in the serum of male septic shock patients. /. Steroid Biochem. 29,435-440(1988). 

Mature males given weekly intraperitoneal injections of 20 or 50 mg Pb/kg BW as lead acetate for 6 weeks vs. 20 or 50 mg sodium acetate/kg BW as controls Dose-dependent increases in blood and sperm lead concentrations. Serum testosterone levels reduced in lead-exposed rats, possibly from generation of reactive oxygen species, and resulting in premature acrosome reaction and reduced sperm oocyte-penetrating capability 39... 

Males and females given 2.32 mg Ni/kg BW daily for 4 days Males had inhibited testosterone levels and reduced growth, while females had increased uterine weights 7... 

For protection of domestic cattle, feeds should contain <0.05 mg diflubenzuron/kg FW. Cottonseed may be added to cattle diets provided that diflubenzuron concentrations in the seed do not exceed 0.2 mg/kg FW and that cottonseed composes <17% of the total diet bulk (Gartrell 1981). Diflubenzuron causes biochemical upset, as judged by lowered testosterone levels in chickens and rats (USEPA 1979), altered glutathione 5-transferase activity in mouse liver (which adversely affects the ability to detoxify foreign substances by way of conjugation Young et al. 1986), and disrupted hydroxylamine activity in human infants (USEPA 1979). Additional research seems needed on biochemical alterations induced by diflubenzuron. No diflubenzuron criteria are currently recommended for protection of avian and mammalian wildlife. All data available suggest that wildlife species are about as tolerant to diflubenzuron as are domestic poultry and livestock however, the wildlife database seems inadequate for practicable criteria formulation. 

If testosterone levels are not suppressed (i.e., greater than 20 ng/dL) after initial LHRH agonist therapy, an antiandrogen or orchiectomy may be indicated. If testosterone levels are suppressed, the disease is considered androgen independent and should be treated with palliative therapy. 

Key diagnostic assessments include ED severity, medical history, concurrent medications, physical examination, and laboratory tests (i.e., serum blood glucose, lipid profile, testosterone level). 

Testosterone-replacement regimens restore serum testosterone levels to the normal range (300 to 1,100 ng/dL). These regimens are indicated for symptomatic patients with hypogonadism as confirmed by low testosterone concentrations. 

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