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1.
J Pediatr Surg ; 32(9): 1344-7, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9314259

RESUMO

Four children were operated on by the transpubic approach for injury to the vagina or urethra and to correct malformations within the pelvis minor. One boy had posttraumatic stricture of the urethra, and a girl presented with disruption of the urethra and vagina. One of two boys who had congenital malformations was treated for epispadias and incontinence; the other for a large urethral diverticulum caused by anal atresia. Total reconstruction was achieved, and no complications of symphysis restoration were observed.


Assuntos
Sínfise Pubiana/cirurgia , Cirurgia Plástica/métodos , Anormalidades Urogenitais , Sistema Urogenital/lesões , Sistema Urogenital/cirurgia , Criança , Pré-Escolar , Cistoscopia , Feminino , Humanos , Masculino , Urografia
2.
Biochem J ; 292 ( Pt 1): 143-7, 1993 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-8503841

RESUMO

A material isolated following pregnenolone incubations with toad (Bufo arenarum) inter-renal tissue at 28 degrees C has been identified as a 3 beta-hydroxy-5-ene analogue of aldosterone (3 beta, 11 beta, 21-trihydroxy-20-oxo-5-pregnen-18-al). The initial identification was made by enzymic and m.s. methods, and structural confirmation was achieved through comparison with chemically synthesized authentic material. The relative efficacy of corticosterone, 18-hydroxycorticosterone and the 3 beta-hydroxy-5-ene aldosterone analogue as aldosterone precursors was evaluated. In the in vitro situation studied, the 3 beta-hydroxy-5-ene steroid was by far the best precursor.


Assuntos
Aldosterona/análogos & derivados , Aldosterona/biossíntese , 3-Hidroxiesteroide Desidrogenases/metabolismo , Aldosterona/metabolismo , Animais , Bufo arenarum , Cromatografia Gasosa-Espectrometria de Massas , Rim/metabolismo
3.
Am J Hypertens ; 5(6 Pt 1): 399-401, 1992 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-1524765

RESUMO

Adrenalectomized, spontaneously hypertensive rats (SHR) were used to test the hypertensinogenic property of recently synthesized 18,19-dihydroxycorticosterone (18,19-Di-OH-B). The steroid was given via Alzet miniosmotic pump, with and without aldosterone. Neither 18,19-Di-OH-B (5 micrograms) nor aldosterone (5 micrograms) increased blood pressure in SHR when given alone; when administered together they resulted in a significant rise in blood pressure. Results indicate a high probability that certain mineralocorticoids, which are inactive by themselves, might play a role in the etiology of hypertension when acting together under physiological conditions.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Glândulas Suprarrenais/fisiopatologia , Hipertensão/induzido quimicamente , 18-Hidroxicorticosterona/farmacologia , Adrenalectomia , Aldosterona/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Combinação de Medicamentos , Masculino , Concentração Osmolar , Ratos , Ratos Endogâmicos SHR , Renina/sangue
4.
Steroids ; 56(11): 566-70, 1991 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1814024

RESUMO

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.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Hiperaldosteronismo/urina , Hipertensão/urina , 18-Hidroxicorticosterona/urina , Adulto , Idoso , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hiperaldosteronismo/complicações , Hipertensão/complicações , Cirrose Hepática/urina , Pessoa de Meia-Idade
5.
J Steroid Biochem Mol Biol ; 37(4): 599-604, 1990 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-2278845

RESUMO

The recently synthesized 18-C-steroid derivative, 19-nor-aldosterone(19-nor- aldo) and 18-hydroxy-19-nor-corticosterone(18-OH-19-nor-corticosterone) possess mineralocoroticoid and hypertensinogenic activity. They and an additional newly synthesized steriod, 18,19-dihydroxycorticosterone[18,19(OH)2-corticosterone], may play a role in the etiology and pathogenesis of disorders thought to be caused by steroids with mineralocorticoid and hypertensionogenic properties. In this study we provide evidence that 19-nor-aldo, 18-OH-19-nor-corticosterone and 18,19(OH)2-corticosterone are produced in vitro by aldosterone-producing adrenal adenomas and adenomas and adenoma of Cushing's syndrome. "silent" adrenal adenomas and the adjacent adrenal tissue. Measurable amounts of these steroids were found in the incubation fluids of adrenal tissues using specific RIAs performed after a sequence of HPLC systems. The rates of production of the three steroids were high in the aldosterone-producing adrenal adenomas and in adrenal hyperplasia compared with in either Cushing's adenoma or "silent" adenoma.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Adenoma/metabolismo , Neoplasias das Glândulas Suprarrenais/metabolismo , Aldosterona/análogos & derivados , Aldosterona/biossíntese , Cromatografia Líquida de Alta Pressão , Síndrome de Cushing/metabolismo , Humanos , Radioimunoensaio
6.
J Steroid Biochem Mol Biol ; 37(2): 261-7, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2268558

RESUMO

Several new 4,19-substituted steroids and previously synthesized corticosteroids were assayed for affinity to type 1 receptors in human mononuclear leukocytes. 11 beta,19-epoxy-4,21-dihydroxypregn-4-ene-3,20-dione (2) was hydrogenated with Pd-C to yield a mixture of all four dihydro derivatives 5, accompanied by 4,21-diacetoxy-11 beta,19-epoxy-3-hydroxypregnan-20-one (6) and 21-acetoxy-11 beta,19-epoxy-4-hydroxypregnane-3,20-dione (7). With hot acetic + p-toluenesulfonic acid 5 underwent rearrangement to 21-acetoxy-11 beta,19-epoxypregn-5-ene-4,20-dione (8) Pd-C hydrogenation of 3,21-diacetoxy-5 beta,19-cyclopregna-2,9(11)-diene-4,20-dione (10) gave 3,21-diacetoxy-5 beta,19-cyclopregn-5-ene-4,20-dione (11) and the 9,11-dihydro derivative of the latter. Treatment of 10 with warm HCl furnished 19-chloro-4,21-dihydroxypregna-4,9(11)-diene-3,20-dione (13). Pd-C hydrogenation of its diacetate 14 afforded the 4,5-dihydro derivative 18, 19-chloro-21-acetoxypregn-9(11)-en-20-one (15), its 4-acetoxy derivative 16 and the 3,4-diacetoxy derivative 17. When tested in a radioreceptor assay in human mononuclear leukocytes the synthesized compounds showed only low relative binding affinities (RBA) to type 1 receptor, the highest being 0.72% for 13 (aldosterone = 100%). For comparison, other RBA in this system were: 19-noraldosterone, 20%; 18-deoxyaldosterone, 5.8%; 18-deoxy-19-noraldosterone, 4.7%; 18,21-anhydroaldosterone, 0.37%; 17-isoaldosterone, 7.6% and apoaldosterone, 4.3%


Assuntos
Desoxicorticosterona/análogos & derivados , Desoxicorticosterona/síntese química , Leucócitos Mononucleares/metabolismo , Receptores de Glucocorticoides/metabolismo , Aldosterona/sangue , Ligação Competitiva , Desoxicorticosterona/química , Desoxicorticosterona/farmacologia , Humanos , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Ensaio Radioligante , Receptores de Glucocorticoides/efeitos dos fármacos , Relação Estrutura-Atividade , Trítio
7.
Endocr Res ; 16(2): 185-91, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2344835

RESUMO

A combination of aldosterone (1 micrograms) with either 18-OH-corticosterone (1 micrograms) or 18-OH-19-norcorticosterone (1 micrograms) injected to adrenalectomized rats indicated an amplification of mineralocorticoid activity as expressed by Na/K ratio in urine. Without aldosterone their mineralocorticoid potency was negligible.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , 18-Hidroxicorticosterona/farmacologia , Adrenalectomia , Aldosterona/farmacologia , Corticosterona/análogos & derivados , Animais , Interações Medicamentosas , Masculino , Potássio/urina , Ratos , Sódio/urina
8.
J Immunoassay ; 11(2): 215-34, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2347927

RESUMO

Two enzyme-linked immunosorbent assays were established and compared for the estimation of plasma aldosterone. In the first method immobilized aldosterone-protein complexes on the ELISA plates compete with aldosterone to be determined for the binding of certain amount of anti-aldosterone antibodies. The sensitivity of this method depends on the protein carrier used to conjugate with aldosterone. In the second method, anti-aldosterone antibodies adsorbed on ELISA plates compete for binding of known amount of the enzyme-labeled aldosterone and aldosterone to be determined. The highly specific rabbit anti-aldosterone antibodies were obtained by injection of aldosterone-oxime thyroglobulin. The detection limit of aldosterone in both methods ranged between 2-20 pg. The proposed assays are suitable for the determination of aldosterone in biological fluids compared with other reported ELISA assays, as well as with RIA.


Assuntos
Aldosterona/sangue , Ensaio de Imunoadsorção Enzimática/métodos , Aldosterona/análogos & derivados , Aldosterona/imunologia , Aldosterona/isolamento & purificação , Animais , Formação de Anticorpos , Especificidade de Anticorpos/imunologia , Ligação Competitiva , Reações Cruzadas/imunologia , Humanos , Masculino , Coelhos , Reprodutibilidade dos Testes
9.
Steroids ; 54(1): 11-9, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2640565

RESUMO

18,21-Anhydroaldosterone 8, 18,21-anhydro-19-noraldosterone 9, and 3 alpha, 5 beta-tetrahydro-18,21-anhydro-19-noraldosterone 13, which may be present in acid-processed urine, were prepared by cleaving their 20-ketal derivatives 2, 3, and 12 with hot mineral acid. Compounds 8 and 9 were also made by direct dehydration of aldosterone 5 and 19-noraldosterone 10 in good yield. The reverse ring opening of 8 to 5 could be carried out in moderate yield with an acetic acid-acetic anhydride-perchloric acid mixture, while an analogous ring opening of 9 gave only a poor yield of 10.


Assuntos
Aldosterona/análogos & derivados , Fenômenos Químicos , Química , Espectrofotometria Infravermelho
10.
Steroids ; 53(1-2): 21-36, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2772968

RESUMO

Infusion of Ring-A-reduced metabolites of aldosterone in adrenalectomized male rats for 4 days revealed that 5 alpha-Ring-A-reduced derivatives, 5 alpha-dihydroaldosterone (5 alpha-DHAldo; 2.5-5.0 micrograms/day), 3 alpha,5 alpha-tetrahydroaldosterone (3 alpha,5 alpha-THAldo; 5-25 micrograms/day), and 3 beta,5 alpha-THAldo (50-175 micrograms/day) possessed intrinsic Na+-retaining activity. The same infusions of 5 alpha-DHAldo, 3 alpha,5 alpha-THAldo, and 3 beta,5 alpha-THAldo, also lowered the urinary excretion of potassium. The 5 beta-Ring-A-reduced derivative 3 alpha,5 beta-THAldo did not demonstrate either of these biological properties. In another set of experiments, on the fourth day of infusion, aldosterone (0.1 microgram/rat) was administered acutely subcutaneously; none of the Ring-A-reduced derivatives altered the Na+-retaining activity of aldosterone. However, in a dose-dependent manner, both 3 alpha,5 alpha-THAldo and 3 beta,5 alpha-THAldo blunted the urinary K+-secretory effect of aldosterone; low dosages of 5 alpha-DHAldo and larger dosages of 3 alpha,5 beta-THAldo did not. Thus, the 5 alpha-reduced derivatives of aldosterone not only lowered urinary Na+ and K+ excretion in their own right, but two of them blunted the kaliuretic response of the parent mineralocorticoid, aldosterone. Further experiments will be required to determine whether these aldosterone metabolites are further metabolized or interconverted during the expression of the regulatory properties described here and whether these properties are physiologically relevant.


Assuntos
Aldosterona/análogos & derivados , Potássio/urina , Sódio/urina , Aldosterona/administração & dosagem , Aldosterona/fisiologia , Animais , Masculino , Ratos , Ratos Endogâmicos
11.
Endocr Res ; 15(1-2): 151-7, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2759047

RESUMO

Urines of patients with primary aldosteronism were extracted, the extract repeatedly chromatographed with reversed phase HPLC. The fractions immunoactive against 18-hydroxycorticosterone antiserum and being more polar than the 18-hydroxycorticosterone were further purified, derivatized and investigated by GC/MS. In this manner the natural occurrence of the 18, 19-dihydroxycorticosterone, which was lately synthetized, in human urine was confirmed.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Corticosterona/análogos & derivados , Hiperaldosteronismo/urina , 18-Hidroxicorticosterona/isolamento & purificação , 18-Hidroxicorticosterona/urina , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Indicadores e Reagentes
12.
J Steroid Biochem ; 31(1): 97-105, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3398535

RESUMO

The 3 beta, 5 alpha-, 3 alpha, 5 alpha- and 3 alpha, 5 beta-tetrahydro derivatives 19, 20 and 27 of 19-noraldosterone (1) were prepared to facilitate the search for these compounds in urine. The diketal 4, consisting of a 2:1 mixture of the 5,6- and 5(10)-ene isomers, was hydrogenated with Pd-C and partially hydrolyzed to 5 alpha, 10 alpha- and 5 alpha, 10 beta-dihydroketals 8 and 10 in a 1:2.5 ratio. Assignment of protons was done with aid of COSY 45 experiments. Compound 10 was reduced with diisobutylaluminum hydride (DIBAH) to 4 products: the 3 alpha- and 3 beta-ol hemiacetals 16 and 15, and the corresponding tetraols 14 and 13. Alternatively, hydrogenation of the 4-en-3-one 2 gave 10, its 5 beta, 10 beta-isomer 21 and the tetrahydro compound 22, in a 4:2:1 ratio. A better way to prepare the 5 beta, 10 beta-series involved microbial conversion of 2 with Clostridium paraputrificum, and the resulting tetrahydrolactone 23 was reduced with DIBAH to the hemiacetal 24. Acid hydrolysis of 16, 15 and 24 afforded 20, 19 and 27, respectively. According to [1H]-NMR, in solution 20 and 24 exist as mixtures of isomers, while 19 appears in one form only. Periodate oxidation converted 19 and 27 into their gamma-etiolactones 18 and 28. EI MS base peaks are different and characteristic for 19, 20 and 27.


Assuntos
Aldosterona/análogos & derivados , Aldosterona/síntese química , Aldosterona/metabolismo , Biotransformação , Clostridium/metabolismo , Espectrometria de Massas , Relação Estrutura-Atividade
13.
Am J Hypertens ; 1(3 Pt 3): 49S-52S, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3415809

RESUMO

Hypertensinogenic properties of recently synthesized 18-OH-19-nor-B and the related 18-OH-B were examined in adrenalectomized, spontaneously hypertensive rats (SHR). Each steroid was given via Alzet miniosmotic pump (2002), with and without aldosterone. Neither 18-OH-19-nor-B (5 micrograms) nor 18-OH-B (5 micrograms) increased blood pressure in SHR when given alone, but when administered together with aldosterone (5 micrograms), which was ineffective by itself, resulted in a significant rise in blood pressure. There is a high probability that certain mineralocorticoids, which are inactive by themselves, are of importance in the etiology of hypertension under physiological conditions.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Glândulas Suprarrenais/fisiologia , Corticosterona/análogos & derivados , Hipertensão/fisiopatologia , 18-Hidroxicorticosterona/fisiologia , Adrenalectomia , Animais , Avaliação Pré-Clínica de Medicamentos , Masculino , Ratos , Ratos Endogâmicos SHR
14.
J Steroid Biochem ; 24(6): 1163-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3736043

RESUMO

19-Noraldosterone has been prepared for biological re-evaluation through an extension of a recent synthesis of 19-hydroxyaldosterone: 21-hydroxy-6 beta,19-epoxy-4-pregnene-3,20-dion-20-ethylene ketal-18,11 beta-lactone (1a) was acetylated and then reduced with zinc-acetic acid-isopropanol to the 19-ol 2b. Treatment with sodium acetate transposed the double bond into conjugation, and 2a thus obtained was oxidized with pyridinium chlorochromate to the 19-oxo compound 3. Decarbonylation to the 19-nor lactone 4 was effected by heating with alkali. Protection of the C-3 carbonyl was achieved by ketalization and the resulting mixture of the 5-ene and 5(10)-ene ketals 5 was reduced with DIBAH to the corresponding mixture of the hemiacetals 6. Acid hydrolysis of the latter afforded 19-noraldosterone (7), accompanied by the 18,21-anhydro ketal 8. 19-Noraldosterone in the solid state exists in the cyclic form 7b, which appears to be also the predominant isomer present under conditions of mass spectrometry. [1H]NMR indicates that in chloroform 19-noraldosterone exists mostly as an equilibrium mixture of structures 7a and 7b. Sodium periodate oxidation furnished the gamma-etiolactone 9, confirming the 17 beta configuration in 7.


Assuntos
Aldosterona/análogos & derivados , Mineralocorticoides/síntese química , Aldosterona/síntese química , Aldosterona/farmacologia , Animais , Anuros , Técnicas In Vitro , Espectrometria de Massas , Métodos , Ratos , Espectrofotometria Infravermelho
15.
Endocrinology ; 118(6): 2505-9, 1986 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3084221

RESUMO

The mineralocorticoid (MC) activities of 19-hydroxyaldosterone (19-OH-Aldo) and 19-nor-aldosterone (19-nor-Aldo) were tested in adrenalectomized male rats. Potency was assessed by three criteria. Overall MC activity is expressed as the ability to decrease the urinary Na+ to K+ ratio; antinatriuretic activity is represented by decreases in the urinary Na+ to creatinine ratio, and kaliuretic activity by increases in the K+ to creatinine ratio. All measurements were made on urine collected 1-3 h postinjection. In this assay, 19-OH-Aldo was 1/100th to 1/140th as active as Aldo, and 19-nor-Aldo possessed MC activity similar to that of Aldo; both steroids possessed antinatriuretic and kaliuretic activities. In contrast, when assayed in vitro in the isolated toad urinary bladder, the natriferic responses of both 19-OH-Aldo and 19-nor-Aldo (10(-8), 10(-7), and 10(-6) M) were not significantly different from those caused by equivalent concentrations of Aldo. 3 beta-Hydroxy-delta 5-Aldo is active as a MC in the adrenalectomized male rat, being 1/20th to 1/35th as active as Aldo, but, in contrast to 19-OH-Aldo, was less active in the isolated toad bladder system. 19-OH-Aldo, 19-nor-Aldo, and 3 beta-hydroxy-delta 5-Aldo could represent important new classes of Aldo analogs.


Assuntos
Aldosterona/análogos & derivados , Natriurese/efeitos dos fármacos , Potássio/urina , Adrenalectomia , Aldosterona/farmacologia , Animais , Bioensaio , Bufo marinus , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Endogâmicos , Sódio/metabolismo , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo
16.
Steroids ; 47(2-3): 205-13, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3564087

RESUMO

A four-step synthesis of 18,19-dihydroxycorticosterone 5c, starting with 19,21-dihydroxy-3,20-dioxopregn-5-ene-18,11 beta-lactone-di-(ethylene ketal) 2, is presented. Reduction of 2 with sodium aluminum bis-(methoxyethoxy)hydride gave 11 beta,18,19,21-tetrahydroxy-pregn-5-ene-3,20-dione-di-(ethylene ketal) 3a. Acetylation furnished the corresponding 18,19,21-triacetate 3b, which on treatment with a mixture of perchloric and acetic acids gave 18,19-dihydroxycorticosterone 18,19,21-triacetate 4b. Mild saponification yielded the title compound which, on the basis of ir and nmr spectra, exists as one C-20 isomer of the hemiacetal structure 5c. Periodate oxidation of 5c gave the expected 11 beta, 19-dihydroxy-3-oxoandrost-4-ene-17 beta, 18-carbolactone 6b.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Corticosterona/análogos & derivados , 18-Hidroxicorticosterona/síntese química , 18-Hidroxidesoxicorticosterona/análogos & derivados , 18-Hidroxidesoxicorticosterona/metabolismo , Acetilação , Isomerismo , Espectrometria de Massas , Espectrofotometria Infravermelho , Relação Estrutura-Atividade
17.
Steroids ; 47(1): 67-81, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3810700

RESUMO

The compounds named in the title have been synthesized from the di-(ethylene ketal) of 21-hydroxy-3,20-dioxo-19-norpregn-5-ene-18, 11 beta-lactone and its 5(10)-ene isomer. Reduction of this mixture 1 with sodium aluminum bis-(methoxyethoxy)hydride furnished the 11 beta, 18, 21-triol 2a. Conversion to the 18,21-diacetate 2b, followed by deketalization to the free dione 3 and hydrolysis, afforded 18-hydroxy-19-norcorticosterone 4a which, in the solid state and probably in solution, has the 18,20-hemiacetal structure. Periodate oxidation of 4a gave 11 beta-hydroxy-3-oxo-19-norandrost-4-ene-17 beta, 18-carbolactone 5a, and acid treatment of 4a or its precursor 2a yielded 18-deoxy-19-noraldosterone 6a. The structure of 5a was confirmed by mass spectrometry and 1H nmr, and compared with that of its C-19 methyl homolog 5b and 19-noraldosterone-gamma-etiolactone 8. In particular, 2-D nmr COSY 45 experiments, affording full 1H line assignments, have rigorously established the "natural" beta (axial) configuration of the C-10 hydrogen in the 19-nor lactones 5a and 8, and therefore also in the related 4a, 6a and 19-noraldosterone 7.


Assuntos
18-Hidroxicorticosterona/análogos & derivados , Aldosterona/análogos & derivados , Corticosterona/análogos & derivados , 18-Hidroxicorticosterona/síntese química , Aldosterona/síntese química , Fenômenos Químicos , Química , Espectroscopia de Ressonância Magnética
18.
Steroids ; 46(6): 1003-10, 1985 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3842021

RESUMO

The relative hypertensinogenic potencies of recently synthesized 19-nor-aldosterone and its precursor 19-OH-aldosterone were assessed in comparison to that of aldosterone (Aldo) in young (6-week-old) adrenalectomized (ADX) spontaneously hypertensive rats (SHR). Infusion of 19-nor-aldosterone for 2 weeks by Alza mini-osmotic pumps caused significant, dose-dependent increases in the systolic blood pressure (BP) of young ADX SHR; dosages of 0.1 and 0.5 microgram/day raised the BP from 127 +/- 2 mmHg to 164 +/- 9 and 180 +/- 11 mmHg, respectively. During this period, control ADX SHR receiving vehicle only remained normotensive. Similar increases in BP were seen only with infusion of slightly higher dosages of Aldo (0.5 and 1.0 micrograms/day). In contrast, 19-OH-aldosterone infused at higher dosages (10 or 25 micrograms/day) caused little change in BP of ADX SHR. Full suppression of plasma renin activity (PRA) was observed with 0.1 and 0.5 microgram/day 19-nor-aldosterone, whereas Aldo caused similar decreases in PRA only at dosages of 0.5 microgram/day and higher. Interestingly, although infusions of 19-OH-aldosterone did not cause a significant change in BP, these dosages (10 and 25 micrograms/day) significantly suppressed PRA. These studies which show that 19-nor-aldosterone is equipotent to Aldo, and perhaps slightly more active in ADX SHR, indicate that 19-nor-aldosterone is a potentially important hypertensinogenic steroid.


Assuntos
Aldosterona/análogos & derivados , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/fisiopatologia , Ratos Endogâmicos SHR/fisiologia , Ratos Endogâmicos/fisiologia , Adrenalectomia , Aldosterona/farmacologia , Animais , Ratos , Relação Estrutura-Atividade
19.
J Steroid Biochem ; 23(2): 207-18, 1985 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-4033120

RESUMO

19-Hydroxyaldosterone (20) and the 3 beta-hydroxy-5-ene analog of aldosterone (HAA) (8) were synthesized from 21-acetoxy-4-pregnene-3,20-dion-20-ethylene ketal-18, 11 beta-lactone (2) as follows: the double bond was transposed from the 4,5 to the 5,6-position by enol acetylation to 3, followed by sodium borohydride reduction. Further reduction of the resulting lactone 4a with diisobutylaluminum hydride (DIBAH) furnished the 20-ketal of HAA 6, from which free HAA (8) and the 18,21-anhydro compound 7 were obtained by acid treatment. The [1H]NMR spectrum of 8 in CDCl3 showed it to be a mixture of two isomeric forms. Correlation with the known aldosterone-gamma-etiolactone (10) was established by periodate oxidation of HAA to the corresponding etiolactone 9 followed by chromic acid oxidation. The preparation of 20 was next effected in the following manner: the diacetate 4b was converted into the 6 beta, 19-oxido compound 13b by addition of hypobromous acid followed by the hypoiodite reaction of the bromohydrin 11. Mild saponification of 13b lead to the corresponding diol 13a, and was followed by selective oxidation to the 3-one 14, readily dehydrobrominated to 15a. Reductive ring opening furnished a mixture of the 19,21-diol 16a and its 5-ene isomer 16b, which was directly converted to the diketal 17. Reduction with DIBAH gave the hemiacetal 18, and hydrolysis of the latter 19-hydroxyaldosterone (20) as a water-soluble solid, accompanied by the 18,21-anhydro compound 19. 19-Hydroxyaldosterone exists in CHCl3 and water as a mixture of mainly two isomers. Periodate oxidation furnished the etiolactone 21. Preliminary results indicate that HAA and 19-hydroxyaldosterone are active mineralocorticoids in the Kagawa bioassay and short-circuit current measurements.


Assuntos
Aldosterona/análogos & derivados , Mineralocorticoides/síntese química , Aldosterona/síntese química , Fenômenos Químicos , Química , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Trítio
20.
J Steroid Biochem ; 22(5): 665-72, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-4010290

RESUMO

Samples containing as precursors either 18-hydroxycorticosterone (18-OH-B) in its M form, or this converted to less polar forms at pH 2 (ACM), or M or ACM enclosed in liposomes from adrenal lipids were incubated at pH 7.4, 4.8 or 3.3 in the presence or absence of quartered rat adrenals for 1 and 2 h. Optimal (10%) yields of aldosterone were obtained when (a) ACM was incubated at pH 4.8 and (b) M enclosed in liposomes was suspended in buffer and shaken without enzyme at pH 3.3. When conditions (a) were supplemented with malate and NADP, 16% of ACM was converted to aldosterone. ACM contained 80% of a fraction which, according to 13C NMR spectroscopy, was identical to 18-deoxyaldosterone (18-DAL). Experiments in which radioactivity from corticosterone (B) or M was trapped by radioinert M or 18-DAL disclosed a pathway comprising sequentially B, 18-OH-B, 18-DAL and aldosterone, and the combined evidence of this work, an enzymatic hydroxylation of 18-DAL to aldosterone.


Assuntos
18-Hidroxicorticosterona/metabolismo , Glândulas Suprarrenais/metabolismo , Aldosterona/análogos & derivados , Aldosterona/biossíntese , Corticosterona/análogos & derivados , Aldosterona/metabolismo , Animais , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Lipossomos/metabolismo , Espectroscopia de Ressonância Magnética , Masculino , Ratos
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