Etiocholanolone

Host-derived (e.g., antigen-antibody complexes, activated complement fragments, inflammatory bile acids, urate crystals, certain androgenic steroid metabolites [e.g., etiocholanolone], certain lymphocyte products)... 

This enzyme catalyzes the hydrolysis of etiocholanolone sulfate to produce etiocholanolone and sulfate. 

AMINOCYCLORRORANE-L-CARBOXYLATE OXIDASE ETIOCHOLANOLONE SULFATASE Evolution of enzyme catalysis,... 

Other steroidal 0-(carboxymethyl)oximes which have been prepared for linkage to BSA include those of 3/3,16a-dihydroxypregn 5-ene-7,20-dione (at C-7), 3-hydroxyoestra-l,3,5(10),7-tetraen-17-one, 3a-hydroxy-5/3-androstan-17-one ( etiocholanolone ), and 17/3-hydroxyandrost-4-ene-3,ll-dione (at C-3). O-... 

The major pathway for the degradation of testosterone in humans occurs in the liver, with the reduction of the double bond and ketone in the A ring, as is seen in other steroids with a A4-ketone configuration in the A ring. This leads to the production of inactive substances such as androsterone and etiocholanolone that are then conjugated and excreted in the urine. 

One inset shows the quantification of THAldo against its 3/>5/Ttetrahydroaldosterone (THAldo) internal standard, and the second inset monitoring derivatized stigmasterol (SS) and its hydrolyzed counterpart, an indicator of derivative stability. Abbreviation An androsterone, CB cholesteryl butyrate, DHEA dehydroepiandrosterone, Et etiocholanolone, PT pregnanetriol... 

Patients with a complete block have almost undetectable excretions of cortisol metabolites. The major urinary steroids are androsterone, etiocholanolone, tetrahydro-... 

Abbreviations An Androsterone, Et etiocholanolone, llfi-OH-An 1 l/ -hydroxyandrosterone, llp-OH-Et 11/I-hydroxyetiocholan-olone, THB tetrahydrocorticosterone, 5aTHB 5a-tetrahydrocorticosterone, THF tetrahydrocortisol, 5aTHF 5a-tetrahydrocortisol... 

For ORD EpialloPDiestriol 16a-OH-androsterone estriol 16a-OH-androsterone 16a-OH-DHEA androsterone etiocholanolone. 

Keto-etiocholanolone 3a-hydroxy-5a-androstan-ll,17-dione KE HB-Hydroxyandrosterone 3a-hydroxy-5 3-androstane-ll, 17-dione OHA HB-Hydroxyetiocholanolone 3a,lla-dihydroxy-5a-androstan-... 

Fig.4.12. Chromatogram scan of dehydroepiandrosterone (1), etiocholanolone (2) and androsterone (3) (see text for details).

Fig.4.13. Separation of DNPH-steroids on a 1-m column of 1.3% BOP on Zipax eluted with isooctane (0.5 ml/min) at ambient temperature. Peaks 1 = epietiocholanolone 2 = androsterone 3 = epiandrosterone 4 = etiocholanolone S = dehydroepiandrosterone. (From ref. 32 with permission of the American Chemical Society, Washington.)...

Chromatography. DNPH-steroid derivatives may be separated on plates of silica gel G (layer thickness, 0.25 nm) with chloroform—carbon tetrachloride (2 1) or chloroform-dioxane (47 3) [30]. The spots may be quantitated directly by spectrodensitometry in situ at 367 nm. Amounts as low as 20-40 ng per spot can be detected. A chromatogram scan of 2.5 jug each of dehydroepiandrosterone, etiocholanolone and androsterone separated with chloroform—dioxane (47 3) is shown in Fig. 4.12. 

ApoSAA, an acute-phase protein, is produced quickly in mice and men in response to a stress (e.g., endotoxin administration, etiocholanolone injection). The apoSAA concentrations rise from less than 1% to more than 25% of the total HDL protein content, depending on the degree of stress (B25, B26). In man, major changes in plasma concentration with disease have been reported, e.g., 100-fold or 1000-fold decreases in concentration with resolution of an acute illness (R18). There are reports that glucose infusion in a normal subject (M22) and in hospital patients (M23) may modify HDL composition and increase plasma apoSAA in HDL and, in vervet monkeys, chair restraint rapidly induces apoSAA production (P3, P5). In cynomolgus monkeys, apoSAA is cleared rapidly from the circulation, more rapidly than apoC-III2 and much more rapidly than apoA-I (B19). 

Fig. 5.22. Gas chromatogram of TMS derivatives of androsterone (A), etiocholanolone (B) and dehydroepiandrosterone (C) standards (left), and of the same compounds obtained from a urine extract (right). Conditions glass column, 6 ft. X 6 mm O.D., 2% GE XE-60 on Gas-Chrom P (100-140 mesh, silanized) argon inlet pressure, 20 p.s.i. 195°C. (Reproduced from Clin. Chem.,...

Occasionally, the parent drug is not excreted in urine at a detectable concoitration, and a knowledge of the m bolic pathways in the particuku species is thus essoitial. An example of this is the identification of 5a-estrane-3p,17a-diol in the urine of horses, or of 19-norandrosterone and 19-nor-etiocholanolone in the urine of humans, to prove administration of the anabolic steroid nandrolone. A few drugs are notable for being excreted in urine almost... 

Disposition in the Body. Testosterone is the androgenic hormone formed in the testes. In man, it is metabolised to 5a-androstane-3a,17)5-diol, androsterone, etiocholanolone, and 5a-androstene-3,17-dione. In the horse, the major metabolites are 5a-androstane-3)5,17a-diol, which is excreted in the urine as the glucuronide conjugate, and the 17)5-epimer which is excreted in the urine as the sulphate conjugate. 

Etilefrine hydrochloride, 606 Etinilestradiol, 596 Etiocholanolone, 1003 Etionamida, 597 Etisazole, 607... 

The composition of the excreted urinary 17-ketosleroids also reveals a close similarity between the hormones of different origin the testis accounts for 30% while the adrenal cortex contributes the remaining 70% of the total urinary 17-ketosteroids [383]. Androsterone, ep a-androsterone, and 5/8-androsterone (etiocholanolone) are the main urinary metabolities of testosterone, and dehydroepiandrosterone is the major urinary 17-ketosteroid derived from the adrenal cortex. 

Formation of sulfates [328] is relatively reversible. This may be due to the fact that the metabolic clearance rate [318] of sulfates is relatively low [389] and their renal excretion inefficient [4]. The conversion of dehydroepiandrosterone sulfate in vivo to androsterone and etiocholanolone glucuronide was demonstrated by Lieberman and co-workers, who administered isotopically labeled dehydroepiandrosterone sulfate and isolated labeled androsterone and etiocholanolone from glucuronicase-hydrolyzed urine [303]. Since in another study by Lieberman [174], the transconjugation from dehydroepiandrosterone sulfate to dehydroepiandrosterone glucuronide without free dehydroepiandrosterone intermediate was declared to be improbable, in vivo equilibrium between dehydroepiandrosterone sulfate and dehydroepiandrosterone seems probable [303]. 

Fig. 3.1 Comparison of the mean serum gentamicin concentration-time curves in control (afebrile) and etiocholanolone-induced febrile subjects (n = 6) following the intramuscular injection of a single dose of gentamicin sulfate (1.5 mg/kg). Note the lower serum gentamicin concentrations in the presence of fever. Neither the renal clearance nor the half-life of gentamicin were significantly changed (Reproduced with permission from Pennington et al. (1975).)...

Adrenal androgens also have a complex metabolic fate DHEA-S is formed in the adrenal cortex or by sulfokinases in the liver and kidney from DHEA and excreted by the kidney. DHEA and DHEA-S can be metabolized by 7a-and 16a-hydroxylases. 17p-Reduction of both compounds forms A -5-androstenediol and its sulfate. Androstenedione can be metabolized to androsterone after 3a- and 5a-reduction. 5P-Reduction results in the formation of etiocholanolone (see Eigure 51-7). These metabolites are conjugated to glucuronides and sulfates, which are then excreted in the urine. 

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