Adrenal function during chronic danazol administration

Drug-induced endocrine blood pressure elevation

Patients with uncontrolled hypertension are at risk for cardiovascular complications. The majority of them suffers from unidentified forms of hypertension and a fraction has so-called secondary hypertension with an identifiable cause. The patient's medications, its use of certain herbal supplements and over-the-counter agents represent potential causal factors for secondary hypertension that are often overlooked. The current review focuses on drugs that are likely to elevate blood pressure by affecting the human endocrine system at the level of steroid synthesis or metabolism, mineralocorticoid receptor activity, or by affecting the catecholaminergic system. Drugs with known adverse effects but where benefits outweigh their risks, drug candidates and market withdrawals are reviewed. Finally, potential therapeutic strategies are discussed.

Peripheral androgen levels in danazol-treated premenopausal women

Eighteen normally menstruating women with endometriosis were treated with 600 mg of danazol daily for 6 months. Blood samples were taken before and after 2, 4, 8, 12, and 16 weeks of treatment and were analyzed for plasma dehydroepiandrosterone sulfate (DHEA-S), dehydroepiandrosterone (DHEA), and testosterone (T) and for serum alanine aminotransferase (ALAT), albumin, creatinine, potassium, and sodium. The basal values of all parameters studied were well within normal reference limits. DHEA-S was significantly increased at 2, 4, and 8 weeks, and DHEA significantly decreased at 8 and 12 weeks of treatment. The ratio between DHEA and DHEA-S was significantly decreased at weeks 4, 8, 12, and 16. T was significantly decreased during the whole period of observation. ALAT was significantly increased at weeks 4, 8, 12, and 16. A slight but significant increase was observed for creatinine and potassium, while no changes were observed for albumin and sodium. Of the two major androgen sources, the adrenal cortex appears to be relatively unaffected; whereas the ovary may be affected to a minor degree. Therefore, it seems likely that the changes observed in DHEA and DHEA-S may be due to minor alterations in renal and hepatic turnover rather than an effect on adrenal steroidogenesis.

Danazol: endocrine pharmacology and therapeutic applications

The options for the medical management of endometriosis have been expanded by the introduction of the synthetic steroid, danazol. The results of large clinical studies suggest that danazol treatment produces significant improvement in the symptoms, signs, and laparoscopic findings of endometriosis. The original studies of the pharmacology of danazol concluded that danazol was a strong antigonadotrophin with mild androgenic effects and no other hormonal properties. Recent studies which emphasize the molecular pharmacology of danazol suggest that this steroid has direct effects on hypothalamic-pituitary function, multiple classes of steroid receptors, gonadal steroidogenesis, and endogenous steroid metabolism. These studies demonstrate that: (1) danazol prevents the midcycle surge of luteinizing hormone (LH) and follicle-stimulating hormone (FSH); (2) danazol does not significantly suppress basal LH or FSH in gonadally intact human beings; (3) in castrated animals danazol can prevent the compensatory increase in LH and FSH; (4) danazol binds to androgen, progesterone, and glucocorticoid receptors; (5) danazol does not bind to estrogen receptors; (6) danazol binds to sex hormone-binding globulin and corticosteroid-binding globulin; (7) danazol inhibits multiple enzymes of steroidogenesis; (8) danazol increases the metabolic clearance rate of progesterone; and (9) metabolites of danazol are hormonally active. Given the complex pharmacology of danazol it is inappropriate to continue to refer to danazol as a "selective antigonadotrophin."U

Review: The mechanism of action of danazol, a novel steroid derivative

Danazol is being increasingly used for the treatment of a wide range of disorders, many of which appear to bear little relation to the condition for which the drug was originally marketed--endometriosis. It has been claimed that this drug acts by means of its antigonadotrophic effects on the pituitary; however, a review of the literature reveals that its efficacy in suppressing normal endometrial growth and in causing atrophy of deposits of endometrium cannot be explained solely on this basis. Recent information indicates that, besides acting at the pituitary level, a major mechanism of action may be by a direct inhibitory effect on target tissue. It is sugggested that such a mechanism would more readily account for the diverse effects of this drug in the treatment of many disorders, all of which appear to be associated with an imbalanced sensitivity of target organs to steroid hormones. A greater understanding of its mechanism of action could lead to an even wider application of this novel drug.

Danazol inhibits human adrenal 21-and 11 beta-hydroxylation in vitro

The effects of danazol on steroidogenesis in vitro in the 16-20 week old human fetal adrenal were examined by studying: 1) danazol binding to adrenal microsomal and mitochondrial cytochrome P-450, and 2) enzyme kinetics of danazol inhibition of the adrenal microsomal 21-hydroxylase and the mitochondrial 11 beta-hydroxylase. The addition of danazol to preparations of adrenal microsomes or mitochondria elicited a type I cytochrome P-450 binding spectrum. Danazol bound to microsomal cytochrome P-450 binding spectrum. Danazol bound to microsomal cytochrome P-450 with a high affinity apparent spectral dissociation constant (KS) of 1 microM and with a lower affinity K's of 10 microM. Danazol bound to mitochondrial cytochrome P-450 with a KS of 5 microM. In addition, danazol competitively inhibited the microsomal 21-hydroxylase (apparent enzymatic inhibition constant KI = 0.8 microM) and the mitochondrial 11 beta-hydroxylase (KI = 3 microM). These findings demonstrate that low concentrations of danazol directly inhibit steroidogenesis in the human fetal adrenal in vitro.

Danazol binding to rat androgen, glucocorticoid, progesterone, and estrogen receptors: correlation with biologic activity

Danazol was found to possess androgenic and glucocorticoid activity in rat bioassays. In contrast, danazol displayed no significant estrogenic activity. In support of these findings, danazol bound to the 8 S androgen receptor of rat prostate cytosol and to the glucocorticoid receptor of rat liver cytosol, but danazol did not bind well to the estrogen receptor of the rat uterus. Finally, danazol bound to the progesterone receptor of the rat uterus, but controversy continues as the whether danazol possesses progestational, antiprogestational, or no progestational effects.