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Biomedical subjects

P Vecsei

Publications and source records attributed to P Vecsei.

At least 19 recordsLinked to original sources
PubMed2000

Increased diurnal plasma concentrations of cortisone in depressed patients.

The enzyme 11-beta-hydroxysteroid dehydrogenase (11-beta-HSD) regulates glucocorticoid activity by converting cortisol into cortisone and vice versa. Frequent signs of major depression are elevated concentrations of circulating cortisol and ACTH. However, no information is available about the activity of 11-beta-HSD in this disorder. Therefore, we compared diurnal plasma concentrations of cortisol and cortisone and their ratios, reflecting 11-beta-HSD activity, in 25 severely depressed patients (Hamilton Depression Scale, 29 +/- 6; 14 men, 11 women, age 22-77 yr; mean, 47 +/- 16) and 30 control persons (20 men, 10 women age 23-85 yr; mean, 51 +/- 19). Cortisol and cortisone were measured at 0900 h, 1100 h, 1300 h, 2000 h, 2200 h, 0100 h, 0300 h, and 0700 h with specific RIAs after extraction. Both cortisol and cortisone concentrations were significantly increased in patients compared with controls (cortisol, 251.7 +/- 113.1 vs. 160 +/- 96.6 nmol/L; cortisone, 32.8 +/- 10.9 vs. 21.9 +/- 10.9 nmol/L). The calculated ratios of cortisol to cortisone were similar in controls and patients. Similar to cortisol, the circadian variation of cortisone was flattened in patients with the ratio of maximal cortisone to minimal cortisone being 1.9-fold higher in controls than in patients. There was no gender-specific difference in cortisone values neither in patients nor in controls. We conclude that in major depression increased cortisol is not due, at least partly, to an altered 11-beta-HSD activity or to a decrease in cortisone.

11-beta-Hydroxysteroid Dehydrogenases↗
PubMed1999

Glucocorticoid receptors in idiopathic nephrotic syndrome.

The variable response of patients with idiopathic nephrotic syndrome (NS) to glucocorticoid (GC) treatment has not been explained. Earlier studies indicated that the response is limited by cellular GC receptors. We investigated these receptors in mononuclear leukocytes of 28 pediatric patients with NS divided into three groups: steroid-sensitive in relapse, steroid-sensitive in remission, and steroid-resistant. Density and binding affinity of GC receptors were determined by a dexamethasone binding assay; no significant differences were found between the three patient groups and between these and healthy controls, although a few patient values fell outside the range of controls. Total and free plasma concentrations of cortisol were low in all three patient groups. A weak positive correlation was found between the number of GC receptors and total plasma cortisol (r=0.36, P=0.03). The results suggest that factors other than GC receptors that mediate the cellular effects of GC are involved in the variable response of NS patients to GC.

Adolescent↗
PubMed1996

[Contamination of intraocular fluid in pars plana vitrectomy].

UNLABELLED: Endophthalmitis after pars plana vitrectomy is rare, with an incidence of 0.05-0.14%. The aim of this study was to evaluate the microbiological situation during pars plana vitrectomy and to ascertain what organisms and how many enter the eye during the operation. PATIENTS AND METHODS: Twenty-five consecutive subjects undergoing primary pars plana vitrectomy were included in the study. Patients were excluded if they had evidence of local or systemic infections or had undergone antibiotic therapy within 3 weeks before surgery. A standard three-port pars plana vitrectomy was performed on each patient. Preoperative smears of the conjunctiva and intraoperative aspirates of the vitreous were taken immediately after sclerotomy, and aspirates of the intraocular fluid at the conclusion of operation. RESULTS: We obtained preoperative smears from the conjunctival sac of all patients, and found that 19 patients (76%) had positive cultures, with coagulase-negative staphylococci as the most commonly isolated organisms, (n = 14; 56%). Vitreous--aspirated immediately after sclerotomy--was sterile in 68% (n = 17). In 32% (n = 8) contamination occurred, the microorganisms isolated being coagulase-negative staphylococci (20%) and Staphylococcus aureus (12%). Five of the samples (20%) of intraocular fluid from the vitreous cavity--aspirated before wound closure--were contaminated, coagulase-negative staphylococci (8%) and Staphylococcus aureus (12%) again being found in culture. In no case did postoperative endophthalmitis develop. CONCLUSIONS: This study demonstrates that bacteria enter the eye during pars plana vitrectomy and that there is a change in the contaminating bacterial species during operation. Even if bacteria remain in the eye after pars plana vitrectomy, postoperative endopthalamitis does not necessarily develop.

Aged↗
PubMed1995

Chronic dexamethasone treatment suppresses hypertension development in the transgenic rat TGR(mREN2)27.

INTRODUCTION: The transgenic rat TGR(mREN2)27 is a monogenetic rat model in hypertension research. Integration of mouse Ren-2 gene into the rat genome led to fulminant hypertension despite suppressed plasma and kidney renin concentrations. Renin is highly expressed in extrarenal tissues, especially throughout the adrenal cortex. AIMS AND METHODS: Because plasma and urinary corticosteroid concentrations are elevated during the development of hypertension in these rats, we investigated the effect of dexamethasone on blood pressure, adrenal renin and steroid metabolism. RESULTS: A daily injection of 100 micrograms/kg dexamethasone for 8 weeks was capable of suppressing the development of hypertension in the transgenic rats. The same regimen did not alter blood pressure in Sprague-Dawley control rats. Plasma concentrations of adrenocorticotrophic hormone (ACTH)-dependent steroids (corticosterone and 18-hydroxydeoxycorticosterone) decreased markedly in both strains treated with dexamethasone, but more pronouncedly in transgenic rats. Surprisingly, plasma aldosterone concentrations increased exclusively in the transgenic rats, and not in control rats, treated with dexamethasone. The decrease in corticosterone and 18-hydroxydeoxycorticosterone production was accompanied by a decrease in the abundance of the messenger RNA (mRNA) encoding the rate-limiting enzyme in steroidogenesis (P450scc cholesterol side-chain cleavage) and a decrease in the mRNA encoding P450c11 beta (11 beta-hydroxylase). The increase in aldosterone was accompanied by a massive increase in the abundance of the mRNA encoding zona glomerulosa-specific P450c11AS (aldosterone synthase), which was not increased in control rats. CONCLUSION: We conclude that ACTH-dependent steroids other than the mineralocorticoid aldosterone are responsible for the development of hypertension in the transgenic rat.

Adrenal Glands↗
PubMed1995

A new subset of mineralocorticoid hypertension with excess of 21-deoxyaldosterone and Kelly's-M1 steroid: clinical and morphological findings.

Ten cases of adrenal adenomas, one case with unilateral adrenal hyperplasia, and another case with apparent bilateral are reported, in whom an alternative pathway of aldosterone via 21-deoxyaldosterone is operative. They all manifested hypertension, low renin activity, low normal potassium values, as well as high urinary excretion rates of 21-deoxyaldosterone and its related metabolite Kelly's-M1 steroid. In all cases, urinary aldosterone metabolites (aldosterone-18-glucuronide and tetrahydroaldosterone) and aldosterone precursor 18-hydroxycorticosterone levels were normal. Hence, the adrenal lesions give rise to hyper-21-deoxyaldosteronism. 21-Deoxyaldosterone is a weak mineralocorticoid, and its elevated production in the presence of normal aldosterone can induce a pathological state of hypermineralocorticoidism. Adrenalectomy resulted in normalization of hypertension in six of eight and amelioration in two of eight cases. Six of seven adenoma cases examined as well as the case of unilateral adrenal hyperplasia were sensitive to ACTH. One of the seven adenomas and, as expected, the case with apparent bilateral hyperplasia were angiotensin responsive. Histologically and electron microscopically, the operated adenomas consisted predominantly of clear cells, characterized by mitochondria with tubulo-vesicular internal structure similar to those of the zona fasciculata (in contrast, our classical Conn's adenoma with normal 21-deoxyaldosterone excretion exhibited a more heterogenous histological appearance and were, in terms of ultrastructure, more similar to cells of the zona glomerulosa). Ultrastructurally and immunocytochemically, the clear cells of 21-deoxyaldosterone adenomas showed features of both the zona glomerulosa and the zona fasciculata and are, hence, considered to be hybrid cells. We conclude that the determination of 21-deoxyaldosterone and Kelly's-M1 should be considered in the diagnosis of mineralocorticoid-induced forms of hypertension, especially when an adrenal adenoma has been detected with an imaging procedure.

Adenoma↗
PubMed1994

Role of 21-deoxyaldosterone in human hypertension.

21-Deoxyaldosterone has been postulated to be a precursor of aldosterone in an alternative biosynthesis pathway and Kelly's-M1 is considered to be its metabolite. In healthy volunteers, the excretion rate of 21-deoxyaldosterone and of Kelly's-M1 are significantly lower than the aldosterone metabolites, aldosterone-18-glucuronide and tetrahydro-aldosterone and than the aldosterone precursor 18-OH-corticosterone. Essential hypertension patients (with low and normal renin) excrete comparable values of 21-deoxyaldosterone and Kelly's-M1 as normotensives. In 66% of aldosterone-producing adenoma cases (APA) and in 60% of idiopathic hyperaldosteronism (IHA) patients, significantly raised values of 21-deoxyaldosterone and Kelly's-M1 were found. The patients with the high excretion rates of both steroids showed only moderately increased values of the aldosterone metabolites, aldosterone-18-glucuronide and tetrahydro-aldosterone, as well as of the aldosterone precursor 18-OH-corticosterone. In contrast, the latter mentioned steroids were excreted in higher amounts in those patients with normal excretion of 21-deoxyaldosterone and Kelly's-M1. Hence, it is suggested that aldosterone is produced alternatively either via 18-OH-corticosterone alone or additionally via 21-deoxyaldosterone. Furthermore, in three cases of "incidentally" discovered adrenal adenomas, 21-deoxyaldosterone and Kelly's-M1 were the only elevated steroids. After adrenalectomy, excretion of 21-deoxyaldosterone and of Kelly's-M1 and blood pressure returned to normal, which proves that these steroids play a role in blood pressure regulation. In essential hypertension, ACTH infusion induced a significant increase of 21-deoxyaldosterone and Kelly's-M1. However, the increase after angiotensin II was 3- to 6-fold higher than after ACTH. IHA patients proved to be more responsive to angiotensin II; and, in contrast, APA cases proved to be more sensitive to ACTH. The data suggest that beside the main route of aldosterone biosynthesis via 11-deoxycorticosterone, corticosterone and 18-OH-corticosterone an alternative pathway exists via 21-deoxyaldosterone in healthy and in hypertensive patients. There are similarities between the regulation of 21-deoxyaldosterone and the regulation of aldosterone. The determination of 21-deoxyaldosterone and its possible metabolite Kelly's-M1 might be appropriate in the diagnosis of mineralocorticoid-induced forms of hypertension, especially when an adrenal adenoma is discovered.

Adenoma↗
PubMed1993

[Unilateral autonomous aldosterone production in hyperaldosteronism suppressible by dexamethasone].

A 21-year-old woman with weight loss, palpitations and facial flush was found to have hypertension (up to 200/130 mm Hg) and mild hyperkalaemia (3.4 mmol/l). Extensive diagnostic tests revealed hyperaldosteronism with contrast storing in the right adrenal gland on scintigraphy after injection of dexamethasone (2 mg daily for one week). The hyperaldosteronism could not be suppressed by dexamethasone. Analysis of venous blood separately from each side pointed to aldosterone production in the right adrenal (right renal vein: 80 ng/dl, drainage area of the right adrenal vein: 114 ng/dl, left renal vein: too low to measure). The right adrenal gland was removed. No adenoma was found histologically. After the operation the aldosterone level was reduced and the blood pressure transiently fell. But both had risen again after 3 months. Renewed tests revealed dexamethasone-remediable hyperaldosteronism. On treatment with hydrocortisone (15-5-5 mg) and 50 mg metoprolol the patient became normotensive without any other medication.

Adrenal Cortex Hormones↗
PubMed1993

Male pseudohermaphroditism caused by nonsalt-losing congenital adrenal hyperplasia due to 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) deficiency.

We observed a boy with ambiguous genitalia and normal testes. Steroid analyses performed during newborn age surprisingly were inconclusive basally and after hCG stimulation, but showed an insufficient testosterone response. Possibly during the early postnatal period the 3 beta-HSD activity in peripheral tissues may have been sufficient to substitute for the deficient 3 beta-HSD activity in the adrenal and gonads. In contrast at 11 and 22 months basal as well as ACTH stimulated levels of 17OHPreg, DHEA and testosterone were typical for a 3 beta-HSD defect.

3-Hydroxysteroid Dehydrogenases↗
PubMed1992

Dose dependent suppression of mineralocorticoid metabolism by different heparin fractions.

One neglected side effect of heparin therapy is the inhibition of adrenal aldosterone production leading to occasionally life-threatening hyperkalaemia. This is only reported with (therapeutic) high doses (greater than or equal to 20.000 IU). The complex interplay of mineralocorticoid metabolites was studied in 29 subjects with unfractionated (UFH) and low molecular weight heparin (LMWH). Both heparins altered mineralocorticoid metabolism in a dose dependent manner. Whereas no effect was observed with UFH 2 x 5000 IU sc/day or LMWH 2500 a FXa U sc/day, higher doses significantly suppressed aldosterone and 18-hydroxycorticosterone production in plasma and urine. Three out of seven patients receiving UFH 3 x 7500 IU sc/day developed hyperkalaemia. This study shows the threshold dosage of UFH leading to suppression of mineralocorticoid metabolism in man and provides information that LMWH as well as UFH can suppress mineralocorticoid production. With respect to therapeutic implications it is important that LMWH at 2500 a FXa U sc/d had no effect on mineralocorticoid metabolism in contrast to UFH at a dosage currently used for prevention of thromboembolism (3 x 5000 IU sc/d).

Adult↗
PubMed1992

The role of the adrenal gland in hypertensive transgenic rat TGR(mREN2)27.

The TGR(mREN2)27 is a new monogenetic rat model in hypertension research. As the mouse Ren-2d renin gene is integrated into their genome, they develop fulminant hypertension between 5 and 15 weeks of age, with blood pressure maxima of 300 mm Hg. Their plasma renin-angiotensin system (RAS) is suppressed, but the transgene is highly expressed in the adrenal gland, so we investigated its possible role in steroid metabolism and the pathogenesis of hypertension. During the phase of hypertension development (between 6-18 weeks), the urinary excretion of deoxycorticosterone (DOC), corticosterone (B), 18-hydroxycorticosterone, and aldosterone is 1.5- to 2.5-fold elevated compared with that in Sprague-Dawley (SD) rats (P less than 0.0005) despite the suppressed plasma RAS. Moreover, the adrenal gland in TGR(mREN2)27 shows an increased maximal response to ACTH stimulation in regard to urinary excretion of DOC (after ACTH, 244 +/- 42 ng/24 h in TGR; 62 +/- 10 ng/24 h in SD; P less than 0.0005) and B (after ACTH, 5144 +/- 346 ng/24 h in TGR; 2607 +/- 324 ng/24 h in SD; P less than 0.0005). Additionally, plasma prorenin in TGR was stimulated more than 10-fold, indicating transgene regulation by ACTH. Since spironolactone treatment did not lower the blood pressure in TGR, hypertension solely due to hypermineralocorticoism is unlikely. Our results indicate that the adrenal steroid metabolism is markedly stimulated in young TGR, and the absolute increase in urinary DOC and B after ACTH injections is enhanced, possibly due to a stimulated local intraadrenal RAS.

18-Hydroxycorticosterone↗
PubMed1992

Mineralocorticoids and mineralocorticoid receptors in mononuclear leukocytes in patients with pregnancy-induced hypertension.

To examine the role of mineralocorticoids in the pathophysiology of pregnancy-induced hypertension (PIH), we studied plasma aldosterone and 18-hydroxycorticosterone levels in 25 women with PIH and 25 normal pregnant women, as controls. Furthermore, we evaluated the mineralocorticoid receptor (MR) status in mononuclear leukocytes in the 2 groups. MR count was significantly (P less than 0.0005) decreased in the PIH group (148 +/- 9 binding sites/cell) compared with the control group (300 +/- 17 binding sites/cell; mean +/- SEM). Plasma aldosterone in women with PIH was 281 +/- 61 pmol/L; in normal pregnant women it was 697 +/- 172 pmol/L (P less than 0.025). Plasma 18-hydroxycorticosterone was also significantly (P less than 0.025) lower (PIH, 1071 +/- 149 pmol/L; controls, 1907 +/- 318 pmol/L). These values were determined at the onset of clinical symptoms of PIH. These results cannot be explained by receptor down-regulation due to higher levels of mineralocorticoids in PIH; a hitherto unknown mineralocorticoid may, thus, be responsible for the hypertension and altered MR status.

18-Hydroxycorticosterone↗
PubMed1992

Effect of sodium restriction on urinary excretion of 19-noraldosterone and 18,19-dihydroxycorticosterone, newly identified mineralocorticoids in man.

19-Noraldosterone, which was recently shown to be synthesized and produced in the human adrenal gland, possesses potent mineralocorticoid activity. 18,19-Dihydroxycorticosterone [18,19-(OH)2B], a possible precursor of 19-noraldosterone, has also been identified in human urine. To elucidate the regulatory mechanism for these newly described steroids, we studied the effect of sodium restriction on the urinary excretion of 19-noraldosterone and 18,19-(OH)2B in six normal subjects. 18,19-(OH)2B and 19-noraldosterone were measured by specific RIAs after purification of the urine extract by high performance liquid chromatography. The 24-h urinary excretion of 19-noraldosterone and 18,19-(OH)2B during the control period were 107 +/- 40 (+/- SE) pmol/day and 5.6 +/- 0.8 nmol/day, respectively. After sodium restriction, the values increased approximately 2-fold (P less than 0.05), to 259 +/- 76 pmol/day and 15.6 +/- 4.5 nmol/day, respectively. Virtually identical responses were seen for aldosterone (from 21 +/- 6.0 to 38 +/- 10 nmol/day), 18-hydroxycorticosterone (from 9.9 +/- 1.1 to 21 +/- 2.8 nmol/day), and 18-hydroxycortisol (from 377 +/- 93 to 554 +/- 129 nmol/day). These observations suggest that 19-noraldosterone and 18,19-(OH)2B are partly under the control of the renin-angiotensin system in normal subjects.

18-Hydroxycorticosterone↗
PubMed1992

Urinary excretion of 19-noraldosterone, 18, 19-dihydroxycorticosterone and 18-hydroxy-19-norcorticosterone in patients with aldosterone-producing adenoma or idiopathic hyperaldosteronism.

Urinary excretion of 19-noraldosterone, 18. 19-dihydroxycorticosterone (18, 19(OH)2-B), 18-hydroxy-19-norcorticosterone (18-OH-19-nor-B), 18-hydroxycorticosterone (18-OH-B), 18-hydroxycortisol (18-OH-F) and aldosterone were measured in 25 patients with primary aldosteronism, 16 with an aldosterone-producing adenoma and 9 with idiopathic hyperaldosteronism. In patients with idiopathic hyperaldosteronism, urinary 19-noraldosterone (207 +/- 51 pmol/day), 18, 19(OH)2-B (21 +/- 4.2 nmol/day) and 18-OH-19-nor-B (879 +/- 213 pmol/day) levels were lower but not significantly different from 19-noraldosterone (263 +/- 56 pmol/day), 18, 19(OH)2-B (40 +/- 8.7 nmol/day) and 18-OH-19-nor-B (1322 +/- 267 pmol/day) seen in patients with aldosterone-producing adenoma. Urinary aldosterone did not differ significantly between patients with idiopathic hyperaldosteronism and those with aldosterone-producing adenoma. Both urinary 18-OH-B and 18-OH-F excretion were significantly higher in aldosterone-producing adenoma (39 +/- 5.2 nmol/day, 1660 +/- 318 nmol/day, respectively) compared with patients with idiopathic hyperaldosteronism (19 +/- 3.3 nmol/day, 541 +/- 93 nmol/day, respectively) (p less than 0.05). Though urinary 18-OH-F and 18-OH-B concentrations were useful markers, the mineralocorticoid steroids which we can only now measure, 19-noraldosterone, 18, 19(OH)2-B and 18-OH-19-nor-B, could not be used to distinguish the two subsets of primary aldosteronism.

18-Hydroxycorticosterone↗
PubMed1991

Severe hypoaldosteronism due to corticosterone methyl oxidase type II deficiency in two boys: metabolic and gas chromatography-mass spectrometry studies.

Infection-triggered, life-threatening salt-loss and hyperkalaemia developed in two male infants with wasting, inappropriately low plasma aldosterone concentrations and elevated plasma renin activity. The presumptive diagnosis of a defective terminal step in aldosterone biosynthesis was made by the presence of large amounts of 11-dehydrotetrahydrocorticosterone and its 18-hydroxylated metabolite (18-OH-THA), free 18-hydroxycorticosterone (18-OH-B) and 18-hydroxytetrahydrocorticosterone in the urine of both patients. The diagnosis of corticosterone methyl oxidase type II (CMO II) deficiency was confirmed by an elevated urinary 18-OH-THA to tetrahydroaldosterone ratio in one boy and by an elevated plasma 18-OH-B to aldosterone ratio in the other boy. Unknown steroids responsible for the salt-loss were not identified. Sodium supplementation but not short-term high dose oral 9 alpha-fluorcortisol (FF) normalized the hyponatraemia in one patient, in whom sodium (Na+)/potassium (K+) co-transport was decreased. Both patients eventually received long-term FF treatment to prevent impairment of longitudinal growth caused by chronic salt-loss. The diagnosis of CMO II deficiency should always be confirmed by elevated precursor-product ratios in urine or plasma, using radioimmunoassays with prior chromatographic separation. Metabolic studies as the short-term response of serum Na+ to high dose FF may not be helpful in differentiating aldosterone biosynthetic defects from end-organ resistance to mineralocorticoids.

Cortisone↗
PubMed1991

Long-term effects of ovariectomy on pituitary-adrenal axis and specific antibody response in rats.

The effects of ovariectomy on morphologically demonstrable characteristics of lymphoid tissue, pituitary, and adrenal glands as well as on plasma ACTH and corticosterone levels and humoral immunity of female Lewis rats were investigated. The present study establishes ovaries as potential regulatory organs upon thymus, pituitary, and adrenal glands in female Lewis rats. In addition to the effects on these important lymphoid organs and endocrine glands, ovariectomy influenced the time course of serum IgM antibody titres against fluorescein isothiocyanate (FITC), but had only moderate effects upon serum IgG antibody titres. In conclusion, the present results suggest that ovariectomy modifies morphological characteristics of the thymus and pituitary-adrenal axis. Furthermore, circulating corticosterone seems to play an important role in regulating antibody formation in intact compared to ovariectomized female Lewis rats, while the influence of thymic mass is far from clear.

Animals↗
PubMed1991

Urinary 18,19-dihydroxycorticosterone and 18-hydroxy-19-norcorticosterone excretion in patients with primary and secondary aldosteronism.

18,19-Dihydroxycorticosterone (18,19(OH)2-B) and 18-hydroxy-19-norcorticosterone (18-OH-19-nor-B) measurements were carried out on the urine of patients with primary aldosteronism (PA), essential hypertension (EHT), and liver cirrhosis with (LC, SA (+)) and without (LC, SA (-)) aldosteronism. The separation of these steroids was performed by extraction and high-performance liquid chromatography followed by radioimmunoassay (RIA) with specific antibodies prepared in our laboratory. 18,19(OH)2-B excretion was elevated in patients with PA (24 +/- 5.9 [+/- SE] micrograms/24 hr; n = 15) and LC, SA (+) (83 +/- 9.4 micrograms/24 hr; n = 8). Values in LC, SA (-) (3.1 +/- 1.2 micrograms/24 hr; n = 8) and in EHT (3.7 +/- 0.4 micrograms/24 hr; n = 42) were found to be similar to those in normal subjects (5.5 +/- 0.9 micrograms/24 hr; n = 30). The values of urinary 18-OH-19-nor-B in PA and LC, SA (+) were higher than in LC, SA (-) EHT and normal subjects (P less than 0.05). Values in the latter three groups, as compared with each other, did not show significant alterations. Nothing is known about the biologic relevance of 18,19(OH)2-B and very little about that of 18-OH-19-nor-B, but the latter steroid seems to potentiate experimental renal hypertension. One can speculate about possible roles of both steroids as precursors of other steroids, e.g., the biologically potent mineralocorticoid 19-noraldosterone. The data obtained suggest that it is not relevant to measure the urinary levels of either steroid in these clinical syndromes.

18-Hydroxycorticosterone↗
PubMed1991

Inhibitory effects of the novel anti-aldosterone compound mespirenone on adrenocortical steroidogenesis in vitro.

Mespirenone (CAS 87952-98-5), the delta 1,2-15 beta, 16 beta-methylene derivative of spironolactone, proved to be a potent and quite specific inhibitor of adrenocortical mineralocorticoid synthesis in vitro. At 10(-4) mol/l concentrations, the production of aldosterone as well as its possible precursor 18-OH-corticosterone was inhibited more than 40% (p less than 0.01), whereas corticosterone was elevated highly significantly. This points to a clearcut blockade of 18-hydroxylase on the main pathway of aldosterone synthesis by mespirenone. Decrease of 18-OH-progesterone- and increase of 21-deoxyaldosterone secretion suggests two additional points of interference on an alternate pathway of aldosterone biosynthesis, i.e. 18- and 21-hydroxylation, respectively. Thus, mespirenone causes an effective all-around inhibition of mineralocorticoid synthesis in rat adrenals. On the contrary, androstendione levels remained virtually unchanged indicating that mespirenone exerts no inhibitory effects on androgen synthesis. In conclusion, mespirenone, due to inhibition of mineralocorticoid synthesis in addition to antagonistic effects on the receptor level, is a candidate for the development of a new, potent and specific anti-aldosterone drug.

Adrenal Cortex↗