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Cadmium (Cd) is a toxic element, which is associated with preeclampsia (PE).We treated pregnant rats with cadmium chloride from gestational days (GDs) 9-12 to introduce the PE-like animal model. Maternal systolic blood pressures (SBPs) and body weights were measured on GDs 0, 5, 10, 15, and 20. Foetuses were delivered by Caesarean section on GD20. Then, the dams were sacrificed and the specimens were obtained. The morphological analysis of the placentae was carried out by haematoxylin and eosin staining examination and immunohistochemistry assay.Our study showed that Cd-treated rats developed PE-like phenotypes, such as hypertension, albuminuria, and foetal growth restriction. Moreover, Cd-injected rats displayed abnormal placental angiogenesis and lower progesterone (P4) levels. We further demonstrated that Cd also inhibited the mRNA and protein expressions of steroidogenic acute regulatory protein, cytochrome P450 cholesterol side-chain cleavage enzyme (CYP11A1), and 3β-hydroxysteroid dehydrogenase 1 (3β-HSD1), which are involved in P4 synthesis in the rat placenta.Our study demonstrates that maternal Cd exposure disrupts the local synthesis of P4 in the placenta, which contributes to the onset of PE in pregnant rats. Supplementing P4 at the early gestational stage may be a promising therapeutic strategy to prevent PE, which requires further investigation.

Background: One of the causes of congenital adrenal insufficiency, a genetically heterogeneous disorder is a mutation in the CYP11A1 gene, which is responsible for the initiation of steriodogenesis by converting cholesterol to pregnenolone. Case: In a now 3 years and 3 months-old girl, adrenal insufficiency was diagnosed in the neonatal period. Clinical exome sequencing for primary adrenal insufficiency revealed a homozygous p.Thr330Met (c.989C>T) variant in the CYP11A1 (NM_000781) gene. Conclusion: Different types of inheritance patterns have been observed in CYP11A1 -related adrenal insufficiency cases. We consider our case is an due to an autosomal recessive inheritance.

In cosmetics and food products, parabens are widely used as antimicrobial agents. Reports have suggested that parabens may be linked to infertility, owing to their effects on basal steroidogenesis properties or their capacity to inflict mitochondrial damage. Despite growing concerns about parabens as endocrine disruptors, it is unclear whether they affect any of these actions in humans, particularly at environmentally relevant concentrations. In this work, an in vitro primary culture of human granulosa cells was used to evaluate steroidogenesis, based on the assessment of progesterone production and regulation of critical steroidogenic genes: CYP11A1 , HSD3B1 , CYP19A1 , and HSD17B1 . The effects of two commercially relevant parabens, methylparaben (MPB) and butylparaben (BPB), were screened. Cells were exposed to multiple concentrations ranging from relatively low (typical environmental exposure) to relatively high. The effect was assessed by the parabens' ability to modify steroidogenic genes, progesterone or estradiol production, and on mitochondrial health, by evaluating mitochondrial activity as well as mtDNA content. Neither MPB nor BPB showed any effect over progesterone production or the expression of genes controlling steroid production. Only BPB affected the mitochondria, decreasing mtDNA content at supraphysiological concentrations (1000 nM). Prolonged exposure to these compounds produced no effects in neither of these parameters. In conclusion, neither MPB nor BPB significantly affected basal steroidogenesis in granulosa cells. Although evidence supporting paraben toxicity is prevalent, here we put forth evidence that suggests that parabens do not affect basal steroidogenesis in human granulosa cells.

Objective: It has been shown in animal models that circadian clock exists in corpora luteum which is essential for maintaining pregnancy. However, it is unknown whether circadian clock exists in corpora luteum and its relation with steroidogenesis in human ovary., Study Design: Human luteinized granulosa cells from patients who underwent in vitro fertilization treatment were purified and cultured in vitro. Accumulation patterns of circadian gene and steroidogenesis-related gene mRNAs in human luteinized granulosa cells were observed during the 48 hours after treatment with human chorionic gonadotropin (hCG) by quantitative PCR., Results: We found that the circadian genes CLOCK, PER2, and BMAL1 were expressed in cultured human luteinized granulosa cells. Among these genes, only expression of PER2 displayed oscillating patterns with a 16-h period in these cells after stimulation by hCG. Expression of CLOCK and BMAL1 did not show significant oscillating patterns. Expression of the steroidal acute regulatory protein (STAR) gene showed an oscillating pattern that was similar to that of PER2. Expression of CYP11A1, HSD3B2, and CYP19A1 increased significantly after hCG stimulation; however, none of these genes displayed significant oscillating patterns., Conclusions: Molecular circadian clock exists in human luteinized granulosa cells and may be related with steroidogenesis in human ovary.

We have earlier shown that cobalt chloride (CoCl2)-induced hypoxia and second messenger 8-bromoadenosine 3', 5'-cyclic adenosine monophosphate (8-Br-cAMP) stimulates vascular endothelial growth factor (VEGF) production in Leydig tumor cell derived MA-10 cells. Both stimuli follow common signal transduction pathways including protein kinase A (PK-A), extracellular regulated kinase 1/2 (ERK1/2), and phosphatidyl inositol-3 kinase/akt (PI3-K/Akt) pathways in the stimulation of VEGF by MA-10 cells. In the present study we investigated the role of CoCl2 and 8-Br-cAMP on steroid production in MA-10 cells. The MA-10 cells were cultured in Waymouth MB 752/1 medium, supplemented with 15% heat inactivated horse serum. Progesterone was estimated by radioimmunoassay (RIA).We report that 8-Br-cAMP stimulated progesterone production by the MA-10 cells whereas CoCl2 inhibited the same. Also, 8-Br-cAMP stimulated steroidogenic acute regulatory protein (StAR) and cytochrome P450 side-chain cleavage enzyme (P450scc) mRNAs expression. However, CoCl2 had no effect on StAR mRNA. Cobalt chloride directly inhibited the expression of P450scc mRNA. The decrease in progesterone production could be attributed to three different mechanisms, (1) an increase in production of reactive oxygen species (ROS), (2) an increase in HIF-1α activity, and (3) ultimately a decrease in the level of cytochrome P450 side chain cleavage (CYT P450scc). Hypoxia has an action and mechanism of action similar to that of gonadotropins on VEGF production, whereas they have a contrasting effect on steroidogenesis. This study suggests that hypoxia could be as important as gonadotropins in regulating Leydig cell steroidogenesis.

The effect of nanoparticle-rich diesel exhaust (NR-DE) on the testicular function and factors related with the biosynthesis of testosterone gene expression were investigated in mice. Male C57BL/Jcl mice were exposed to clean air, low-dose NR-DE (Low NR-DE), high-dose NR-DE (High NR-DE) or filtered diesel exhaust (F-DE) for 8 weeks. We found that the mice exposed to High NR-DE had significantly higher testosterone levels than those in the control and F-DE groups. To determine the effects of NR-DE on testicular testosterone production, interstitial cells dissected from the male mice which were exposed to NR-DE, F-DE, or clean air for 8 weeks were incubated with or without human chorionic gonadotropin (hCG; 0.1 IU/mL) for 4 h. The concentrations of testosterone in the culture media were measured. The testosterone production was significantly increased in with or without hCG of High NR-DE exposed group, and significantly decreased in both with or without hCG of F-DE exposed groups. Moreover, several genes, which is associated with testicular cholesterol synthesis, HMG-CoA, LDL-R, SR-B1, PBR, and P450scc, P450 17α, and 17β-HSD were determined in the testis of adult male mice. The results showed High NR-DE exposure significantly increased the expression of these genes. Whereas, the levels in the F-DE exposure group returned to those in the control group, implicating that the nanoparticles in DE contribute to the observed reproductive toxicity. We conclude that enhancement of testosterone biosynthesis by NR-DE exposure may be regulated by increasing testicular enzymes of testosterone biosynthesis.

Rats of the Hatano high-avoidance (HAA) and low-avoidance (LAA) strains have been genetically selected on the basis of their two-way active avoidance behavior, and have different endocrine responses to stress. The present study focused on the adrenal steroid hormone responses of the Hatano strains and identifies differences in regulation of the adrenal cortex in vitro of HAA and LAA rats. Although incubation with prolactin (PRL) and/or adrenocorticotrophic hormone (ACTH) resulted in a dose-dependent increase of corticosterone and progesterone release by adrenal cells from both HAA and LAA male rats, the responses were markedly increased for adrenal cells from LAA rats as compared with HAA rats. This finding suggested that adrenal glands of HAA rats are less sensitive to PRL and/or ACTH than adrenals from LAA rats. Several possible intra-adrenal regulators were investigated. The basal level of expression of steroidogenic acute regulatory protein (StAR) and the long form of the PRL receptor (PRLR-L) mRNAs was higher in adrenals of LAA rats. ACTH treatment of adrenal cells from HAA rats resulted in statistically significant increases in melanocortin receptor 2 (MC2R) mRNA expression, while neither ACTH nor PRL altered MC2R mRNA expression in adrenal cells of LAA rats. Conversely, the increase in PRLR-L mRNA expression induced by PRL was observed only in adrenal cells from LAA rats. Treatment of adrenal cells with PRL and/or ACTH increased the expression of StAR and CYP11A1 mRNAs for both Hatano strains. However, the induction of StAR mRNA expression was higher in LAA rats, but the CYP11A1 response was lower. These findings indicate that adrenal cells of the LAA strain have higher sensitivity to secretagogues than those of the HAA strain. These results suggest that PRL may also be important in stimulating secretion of adrenal steroid hormones.

Cytochrome P450 side-chain cleavage (CYP11A1) catalyzes the first and "rate-limiting" step in steroidogenesis, the conversion of cholesterol to pregnenolone. In an effort to gain further insight into the structure/function relationship of this key enzyme, CYP11A1 was characterized in the Cape baboon (Papio ursinus), a species closely related to humans. Baboon cDNA was isolated from adrenal tissue and direct sequence analysis showed mature baboon and human CYP11A1 share 98% deduced amino acid homology. The cDNA was subsequently amplified and two recombinant constructs, CYP11A1a and CYP11A1b, were cloned. Sequence analyses of the constructs revealed four amino acid substitutions. The constructs were expressed in nonsteroidogenic mammalian COS-1 cells with 25-hydroxycholesterol as substrate. Apparent Km values of 1.62 and 4.53 microM were determined for CYP11A1a and CYP11A1b, respectively. Homology modeling revealed that the lower substrate affinity of CYP11B1b could be attributed to an I98K substitution, which lies between the B and C helices, providing further evidence for the importance of this domain in the catalytic activity of CYP11A1.

The effects of melatonin on steroidogenesis and gene expression of CYP 11A, CYP 17, and CYP 19 were investigated using a porcine antral follicle culture model. Follicles were cultured with melatonin at doses of 10, 50, and 100 ng/mL in the presence and absence of an optimum dose of luteinizing hormone (LH) (100 ng/mL) for a period of 30 hours. It was found that melatonin stimulated progesterone production both in the presence and absence of LH. Androstenedione production was stimulated by melatonin at the highest dose of 100 ng/mL but melatonin had an inhibitory effect in the presence of LH. Estradiol production was not affected by melatonin alone, while in the presence of LH it showed a bimodal effect. Expression of genes for steroidogenic enzymes specific for the production of progesterone, androstenedione and estradiol (CYP 11A, CYP 17, and CYP 19, respectively) were also analyzed in the theca of follicles cultured with and without LH. Results showed an inhibition of CYP 11A and CYP 17 expression both in the presence and absence of LH. However, the expression of CYP 19 was not affected. Our results indicate that melatonin modulates ovarian theca cell steroidogenesis at the molecular level and this modulation may be mediated by its effects on the transcriptional activity of the steroidogenic enzymes.

Cytochrome P450scc catalyzes the important first step in the steroid synthesis pathway; however, it is clear that additional factors regulating the temporal and spacial specific expression of the CYP11A1 gene remain to be identified. To isolate novel transcription factors that regulate this gene, a cis-acting element of the 5'-flanking region from nucleotides -155 to -131 (-155/-131) was used to screen a human placental lambda gt11 cDNA expression library, and an interacting clone was isolated. The open reading frame of the cDNA encodes several domains that are characteristic of transcription factors including an acidic region, a region rich in prolines and three zinc-finger motifs. Expression of the cDNA by in vitro transcription/translation and by transient transfection in HeLa cells yielded a protein of 132 kDa, which concurs with the predicted size. Transfection of the cDNA in placental JEG-3 and adrenal NCI-H295 cells, stimulate expression of a reporter construct controlled by the P450scc gene 5'-flanking region from nucleotides -1676 to +49. This transcriptional regulating protein of 132kDa (TReP-132) when expressed in HeLa cells was demonstrated to interact with the -155/-131 region in bandshift analysis, and tandem copies of this region was shown to confer activation of the heterologous HSV thymidine kinase minimal promoter. Coexpression of CBP/p300 with TReP-132 further increased promoter activity, and the proteins were demonstrated to interact physically. RNA analysis demonstrated the highest levels of expression in the adrenal cortex and testis; and transcript expression is also found in the steroidogenic JEG-3, NCI-H295, and MCF-7 cell lines, but not in non-steroidogenic HepG2 and HK293 cells. Subsequently it has been shown that TReP-132 interacts with steroidogenic factor-1 (SF-1) through specific domains; and along with the interaction with CBP/p300 these factors are postulated to form a complex to regulate expression of the P450scc gene.

During fetal life, it is critical that there is coordinate regulation of the growth, zonation and differentiation of the fetal adrenal cortex to ensure that cells in key tissues and organs are exposed in a programmed temporal sequence to the actions of glucocorticoids. Glucocorticoids are essential for maturation of key target organs before birth, including the lung, brain, liver, gut, kidney and adrenal, and the prepartum increase in glucocorticoid synthesis and secretion by the fetal adrenal gland is critical for the successful transition to postnatal life. It is also evident that premature or abnormal exposure of embryonic or fetal tissues to glucocorticoids during critical windows of development can irreversibly alter the programmed development of organ systems. Premature or abnormal exposure of the fetus to excess glucocorticoids may occur either as a consequence of endogenous stimulation of the fetal hypothalamo-pituitary-adrenal axis (HPAA) or as a consequence of exposure to exogenous glucocorticoids in a therapeutic context. Administration of synthetic glucocorticoids to women at risk of preterm labour, for example, is a routine clinical practice designed to improve respiratory function and neonatal outcome. It is clearly important to understand what endogenous factors regulate the growth and functional maturation of the adrenal cortex during development and the consequent likelihood of exposure of developing tissues to excess corticosteroids. To date, investigations have centred on the role of ACTH 1-39 in the stimulation of adrenal growth and steroidogenesis in long gestation species, such as the primate and sheep, where maturation and differentiation of organ systems occurs predominantly before birth. In this review, we will focus on the evidence that in addition to ACTH 1-39, other pro-opio-melanocortin (POMC) derived peptides, which are synthesized, processed and secreted by the fetal pituitary, play a role in the coordinate regulation of the specific phases of growth and functional development of the fetal adrenal gland in vivo. We will discuss our recent findings on the direct in vivo actions of N-POMC 1-77 and separately, insulin like growth factor II (IGF-II), as adrenal growth factors. These studies provide an understanding of the separate regulatory mechanisms which control activation of adrenal growth and stimulation of adrenal steroidogenesis in the late gestation fetus.

Possible involvement of salt-inducible kinase (SIK), a serine/threonine protein kinase first cloned from high K+-diet treated rat adrenal glands, in the regulation of steroidogenesis was investigated. Y-1 cells, when treated with ACTH, underwent a rapid change in SIK's mRNA content. It reached the maximum within a few hours and returned to the base after 8 h. In contrast, the levels of mRNAs for CYP11A and StAR protein reached the maxima after 8 h. The SIK's mRNA induction failed to occur in ACTH-, forskolin- or 8-Br-cAMP-treated Kin-7 cells, a mutant cell line of Y-1 with defective cAMP-dependent protein kinase A (PKA). Y-1 cells that overexpress SIK, when treated with ACTH, had significantly repressed levels of mRNAs for CYP11A and StAR protein. Therefore, SIK might have a negative effect on the CYP11A- and StAR protein-gene expression in the early phase of ACTH-mediated steroidogenesis. To further explore the mechanisms underlying this phenomenon, we examined intracellular distribution of the green fluorescence protein (GFP)-tagged SIK. When GFP-SIK was introduced into HeLa cells, the fluorescent signals were detected in the nucleus. In Y-1 cells GFP-SIK was detected both in the nucleus and cytosol, and the signal in the former moved to the latter after ACTH-treatment. The nuclear/cytosol re-distribution of GFP-SIK was also observed in forskolin- or 8-Br-cAMP-treated Y-1 cells, but not in Kin-7 cells. These results suggest that the intracellular re-distribution of SIK in Y-1 cells may depend on the cAMP/PKA signaling pathway and has an important regulatory role in the ACTH-mediated steroidogenic gene expression.

There are two main regulatory sites of aldosterone biosynthesis, the early rate-limiting step by the P450scc and the final steps by the P450aldo. We have already demonstrated that, during gestation, activity and mRNA levels of P450aldo are increased. It has been shown that changes in sodium and potassium in the diet modulate the expression of P450aldo in adrenal zona glomerulosa (ZG). In the present study, we compared the effects of low-sodium (Na+) and high-potassium (K+) diet on the expression of enzymes controlling aldosterone synthesis during gestation. Pregnant and nonpregnant rats were randomly assigned to control group or to group receiving low Na+ or high K+ diet during the last week of pregnancy. By the end of the treatment, the two diets induced increases of plasma aldosterone and P450aldo mRNA levels in nonpregnant and pregnant rats. However, plasma renin activity and P450scc mRNA levels were only in the pregnant group fed the low Na+ diet. High K+ diet had no effect on these parameters. We, thus, suggest that the renin-angiotensin system and the enzymes implicated in aldosterone synthesis are differently regulated during gestation.

P450scc and 3beta-HSD cDNA were isolated from a zebrafish lambda gt10 cDNA library using trout SCC and 3beta-HSD cDNA as the probes. The zebrafish SCC cDNA encodes a protein of 509 amino acids, which shares a 78% similarities with the trout SCC and 58% with the human SCC. As for 3beta-HSD, two forms of cDNA were isolated, termed HSD 5 and HSD 17, which may have resulted from alternative splicing. HSD 5 and HSD 17 encode proteins of 374 and 341 amino acids respectively. Both share 77% amino acid similarities with trout 3beta-HSD and 53% similarities with the mouse 3beta-HSD. Zebrafish has been increasingly used as a genetic model system to study organ development and to investigate human diseases. The cloning and the characterization of zebrafish P450scc and 3beta-HSD should facilitate study of steroidogenesis and human disease associated with steroid imbalance.

OB protein leptin inhibits the secretion of cortisol in primary cultures of bovine adrenocortical cells and down-regulates 17alpha-hydroxylase cytochrome P450 mRNA expression. To analyze if leptin regulates other major enzymes involved in adrenal steroidogenesis we tested its effect on mRNA expression for two further key enzymes, C21-hydroxylase (P450C21) and side-chain cleavage enzyme (P450SCC). Cultured bovine cortical cells were stimulated for 24 hours with 10 nM ACTH, with 10 nM ACTH plus 100 ng/ml leptin or left unstimulated as controls. Stimulation with ACTH led to a 1.75-fold increase of P450C21 mRNA and a 3.31-fold increase of P450SCC mRNA compared to unstimulated controls. Addition of leptin led to a reduction of ACTH-stimulated mRNA accumulation of 73% for P450C21 and of 45% for P450SCC. We therefore suggest that leptin reduces cortisol synthesis in the adrenal by down-regulating the steroid producing enzyme cascade in the cortical cell.

The mechanism of the altered adrenal responsiveness during chronic stress was studied by analysis of ACTH and Ang II responses and the expression and activity of steroidogenic enzymes in the adrenal cortex of rats subjected to repeated immobilization (2 hr/day for 14 days), or repeated i.p. injection of 1.5 M NaCl. Concomitant with increased pregnenolone production and reduced aldosterone secretion by isolated adrenal glomerulosa cells of chronically stressed rats, P-450scc mRNA were increased and P-450aldo mRNA levels were decreased in adrenal zona glomerulosa. Consistent with elevated plasma corticosterone levels, isolated adrenal fasciculata cells from stressed rats showed higher cAMP, pregnenolone and corticosterone responses to ACTH. Adrenal fasciculata area and levels of P-450scc, but not those of P-450(11s) hydroxylase were significantly increased. The effects of repeated stress on adrenal steroidogenesis were mimicked by repeated ACTH injections. The half life of corticosterone in plasma measured with [3H]corticosterone was increased in stressed rats but not in ACTH injected rats. This study shows that chronic stress leads to a) inhibition of mineralocorticoid secretion due to inhibition of the late biosynthetic pathway, and b) increased circulating glucocorticoids due to increased ACTH receptor activity, expression and activity of the early pathway, and decreased glucocorticoid clearance. Altered adrenal glomerulosa and fasciculata function, but not changes in glucocorticoid clearance, are probably mediated by increased ACTH secretion during chronic stress.

To assess the direct effect of growth hormone and growth hormone-releasing hormone on gene expression of steroidogenic enzymes and production of progesterone, 17-hydroxyprogesterone (17-OHP) and estradiol, we cultured luteinizing granulosa cells with or without follicle-stimulating hormone (FSH), growth hormone and growth hormone-releasing hormone at different concentrations. Luteinizing granulosa cells were obtained from women undergoing an in vitro fertilization program in the Department of Obstetrics and Gynecology, S. Raffaele Scientific Institute, Milan, Italy. At a concentration of 1 microgram/ml, FSH significantly increased estradiol production (2.1 +/- 0.7-fold the control value; p < 0.05 vs. control) and progesterone production (3.5 +/- 2.0-fold the control value; p < 0.05 vs. control). Growth hormone was effective on estradiol, progesterone and 17-OHP at 1 microgram/ml, enhancing estradiol production (1.3 +/- 0.2-fold the control value; p < 0.05 vs. control), progesterone production (2.5 +/- 1.0-fold the control value; p < 0.05 vs. control), and 17-OHP (1.4 +/- 0.2-fold the control value; p < 0.05 vs. control). Growth hormone-releasing hormone increased estradiol production (1.5 +/- 1.2-fold the control value) and progesterone production (1.3 +/- 0.8-fold the control value), but not significantly. No effects by growth hormone-releasing hormone were seen on 17-OHP production. FSH, growth hormone and growth hormone-releasing hormone did not increase P450scc and P450 aromatase mRNAs, whereas FSH increased P450c17 mRNA to 150% at 100 ng/ml and 1 microgram/ml, growth hormone increased it to 230% at 100 ng/ml and to 200% at 1 microgram/ml, and growth hormone-releasing hormone increased it to 140% at 100 ng/ml and to 190% of control values at 1 microgram/ml. These results indicate a direct effect of growth hormone on steroidogenesis by increasing P450c17 mRNA accumulation and progesterone, 17-OHP and estradiol production.

CYP17 is not expressed in adult mouse adrenal glands but is expressed in a subset of fetal adrenocortical cells, indicating the potential to produce both corticosterone and cortisol during murine embryogenesis. CYP11A is expressed in the fetal adrenal but also in developing hindgut, which will form the colon, and in cells located beneath the skin of the embryo. Novel sites of expression of CYP17 and CYP11A in the mouse embryo suggest potential physiological roles for local production of steroids in diverse organs systems during development.

The synthetic androgen methylandrostenediol (MAD) and the naturally occurring one, testosterone, both bring about hypertensive cardiovascular disease when chronically administered to rats. The pathogenesis of this form of experimental hypertension is thought to result from inhibition of steroid 11 beta-hydroxylase activity. In contrast to the above androgens, 19-nortestosterone, androstenedione and dehydroepiandrosterone (DHEA) have been reported to be without effect in elevating blood pressure. To examine the mechanism(s) involved, we have in this study compared the effects of a number of androgens on adrenal cytochrome P- 45011 beta enzyme and mRNA steady state levels. These parameters were also correlated with the ability of adrenal mitochondria isolated from these groups to hydroxylate 11-deoxycorticosterone (DOC) to corticosterone and 18-hydroxy-11-deoxycorticosterone (18-hydroxy-DOC). Rats treated for seven days with 10 mg per day of dihydrotestosterone, testosterone, 19-nortestosterone or MAD showed a profound decrease in cytochrome P-45011 beta mRNA levels (to less than 20% of controls). This was accompanied by similar changes in both the level and activity of the enzyme. Androstenedione and DHEA were less potent in effecting these changes. In addition, for MAD and testosterone we tested the dose dependence of these changes and found that increasing doses (0.1 mg to 10 mg per day) of either androgen caused progressive decreases in the parameters measured. To assess selectivity we also determined the steady state level of cytochrome P-450scc mRNA in rats treated with the various androgens. In contrast to what was found with cytochrome P-45011 beta, the mRNA transcript for cytochrome P-450scc was equal to or above control levels. We conclude that, in general, the extent of inhibition of cytochrome P-45011 beta enzyme and mRNA level by a given androgen correlates with its reported facility in producing hypertension in rats. Increased secretion of DOC continues to be a likely mechanism for the development of this hypertension but with some androgens extra-adrenal effects may be involved.