Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0338671 (Steroids)
 9,479 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A fluorimetric enzymeimmunoassay has been developed having the sensitivity (500 fg/assay tube) required for determining testosterone concentrations in female plasma and saliva samples. The assay featured a solid-phase antiserum raised against an 11 alpha-hydroxytestosterone-11-hemisuccinate bovine serum albumin conjugate, an 11 alpha-hydroxytestosterone-11-hemisuccinate horseradish peroxidase conjugate as the "enzyme label", and p-hydroxyphenylacetic acid as the substrate for the development of fluorescence. Specificity was ensured by "extracting" testosterone from samples with a solid-phase anti testosterone-3-/0-carboxymethyl/-oxime serum. The assay was shown to satisfy accepted validation criteria providing results in good agreement with routine radioimmunoassay procedures in both plasma (r greater than 0.98, n=28) and saliva (r greater than 0.99, n=28). In saliva samples collected at 2 hourly intervals by normal healthy women (n=5) testosterone concentrations showed a well defined circadian rhythm: the mean testosterone concentration in early morning samples (174 pmol/litre) fell by 83% in late evening collections. In healthy female volunteers (n=7), mean daily throughout one complete cycle ranged from 50 to 218 pmol/litre. Following dexamethasone administration testosterone concentrations in plasma fell by approximately 50%, and salivary concentrations were undetectable after one hour. This enzymeimmunoassay may be useful in studies of female infertility.
Steroids 1980 Jan
PMID:A sensitive enzymeimmunoassay with a fluorimetric end-point for the determination of testosterone in female plasma and saliva. 699 May 57

This paper reports the development of a solid-phase enzymeimmunoassay for quantitating levels of norethisterone (norethindrone) in small portions of plasma (10 mcliters) and saliva (100 mcliters). The assay system uses an antiserum against norethisterone-11 alpha-hemisuccinyl/bovine serum albumin conjugate, prepared by coupling to cyanogen bromide-activated cellulose. Enzyme label was norethisterone/horseradish peroxidase conjugate. The assay's sensitivity at its lower limit was 3 pg/tube. When these enzyme immunoassay results were compared with a standard radioimmunoassay, good agreement for both plasma (r=.99) and saliva (r=.98) was found. Healthy volunteers were then given a norethisterone-containing contraceptive orally, and their plasma and saliva levels of the agent were measured. The plasma and salivary values both peaked at 1 hour postadministration. Maximum salivary levels were but 3% of plasma levels; however, since they reflected, in ratio, concentrations in plasma, salivary measurements may prove useful in fertility control programs and pharamacokinetic studies.
Steroids 1980 Apr
PMID:A sensitive solid phase enzymeimmunoassay for norethisterone (norethindrone) in saliva and plasma. 699 May 58

Subcellular fractions of pregnant rabbit ovary at day six of gestation catalysed the formation of progesterone from pregnenolone (3 beta-hydroxy-5-pregnen-20-one). The microsomal fraction was found to have maximum activity. The enzyme needed hydrogen peroxide for its activity. In vitro studies using horseradish peroxidase also showed similar conversion and this was stimulated 200% in the presence of ascorbic acid. Ascorbate thus appears to perform a catalytic role in this conversion. The importance of peroxidase in luteal steroidogenesis is indicated.
Steroids 1982 Nov
PMID:Studies on peroxidase-catalyzed formation of progesterone. 718 86

The mitochondrial fraction of diethylstilbestrol-treated rat uteri, known to contain an estrogen-induced peroxidase, was able to catalyze the release of 3H2O from either [2-3H]- or [4-3H]estradiol. Hydrogen peroxide added to this system increased the yield of 3H2O but had no effect on mitochondrial preparations from ovariectomized rat uteri having only very low peroxidase activity. The reaction was inhibited by catalase and also occurred with lactoperoxidase in the presence of H2O2 but 2-hydroxyestradiol was not detected in any of these experiments. Under similar conditions, tyrosinase catalyzed the formation of the catechol estrogen with loss of 3H from [2-3H]- or [2,4,6,7-3H]- but not [4-3H]- or [6,7-3H]estradiol. It is proposed that the formation of 3H2O from 3H-labeled estradiol in the estrogen-treated rat uterus may occur by a peroxidative mechanism which does not necessarily result in hydroxylation of the steroid.
Steroids 1980 May
PMID:Formation of 3H2O from [2-3H]- and [4-3H] estradiol by rat uteri in vitro: possible role of peroxidase. 739 59

Sexual differentiation occurs prenatally in guinea pigs but extends into the postnatal period in rats. Steroids affect the development of two motoneuron nuclei of the rat lumbar spinal cord that innervate sexually dimorphic perineal muscles. The spinal nucleus of the bulbocavernosus (SNB) innervates the bulbocavernosus (BC) and levator ani (LA) muscles while the dorsolateral nucleus (DLN) innervates the ischiocavernosus (IC). In male rats, perinatal testosterone prevents degeneration of these muscles and results in a sex difference in both motoneuron size and number in adulthood. For comparative purposes, we examined the guinea pig motoneurons innervating these muscles, as well as those innervating the retractor penis (RP) and retractor clitoris (RC), muscles that have no counterpart in rats. Injections of horseradish peroxidase localized the BC/LA and IC motoneurons of guinea pigs to discrete columns in spinal levels L6 and S1, with the BC/LA motoneurons occupying a more medial position. The RP/RC motoneurons were found in L5. Motoneuronal soma area was larger in males in all examined motor pools, as was nuclear area of BC/LA and IC motoneurons. Although raw counts suggested a sex difference in cell number in the motor columns containing BC/LA and IC motoneurons, either of two different correction procedures for split nuclei error eliminated the sex difference in cell number, emphasizing the importance of such corrections when comparing neurons of different size.
 ...
PMID:Motoneurons innervating guinea pig perineal muscles are sexually dimorphic in size but not number. 749 93

A direct competitive heterologous enzyme-linked immunosorbent assay (ELISA) was developed and validated to determine follicular fluid estradiol levels of different antral follicular sizes (small, medium, and large) obtained from the ovaries of heifers in the follicular phase of the estrous cycle. Polyclonal antiestradiol antibodies were raised in New Zealand White rabbits using 6-keto-1,3,5(10)-estratriene-3,17 beta-diol 6-carboxymethyloxime: bovine serum albumin as immunogen and characterized by the usual methods. Horseradish peroxidase conjugated to 1,3,5(10)-estratriene-3,17 beta-diol 3-hemisuccinate was used as a label. The concentration range used for the standard curve was 0 to 1 ng per well. The low detection limit of the technique was 0.3 pg per well with a sensitivity at 50% binding of 93.62 pg per well. Intraassay and interassay CV (%) were < 5.3% and < 7.0%, respectively (n = 10). The recovery rate of the known estradiol concentrations added to follicular fluid averaged 96.1 +/- 1.3%. Compared with a radioimmunoassay (RIA), the values of ELISA were highly correlated (r = 0.99, P < 0.005). This assay was used to quantify follicular fluid estradiol concentrations without previous extraction in three antral follicular sizes; small (< 5 mm), medium (5.1 to 10 mm), and large (10.1 to 20 mm). The mean +/- SE follicular fluid estradiol concentrations were 77 +/- 5.2 ng/ml (n = 490) in small follicles, 111 +/- 19 ng/ml (n = 65) in medium follicles, and 496 +/- 144 ng/ml (n = 45) in large follicles.(ABSTRACT TRUNCATED AT 250 WORDS)
Steroids 1993 Jul
PMID:Determination of follicular fluid estradiol levels by enzyme-linked immunosorbent assay. 821 80

The glycoprotein corticosteroid-binding globulin (CBG) migrates as doublet bands in PAGE and SDS-PAGE, and as numerous bands in isoelectric focusing (IEF). This study deals with the origin of this heterogeneity. Desialation of rat CBG with neuraminidase does not abolish the doublet in either PAGE or SDS-PAGE, indicating that the doublet does not arise as a result of differences in sialic acid residues. Treatment of the separated upper and lower variants of native CBG with N-glycosidase F (PNGase-F) shows a differential pattern of deglycosylation over time indicating either differences in the number, type, or location of sugars attached to each of the variants. Rate of deglycosylation is quicker and more extensive for the upper variant when compared to the lower variant. PNGase-F treatment of 1% SDS-denatured CBG does not abolish the CBG doublet seen in SDS-PAGE, indicating that there is variation in the protein moiety. Sugars could not be detected on PNGase-F treated CBG using either wheat germ aglutinin horse radish peroxidase conjugate, concavilin-A HRP conjugate, or the digoxigenin glycan detection system. While the results clearly show differences in glycosylation between the CBG variants, differences in the protein moiety may also occur to give rise to the heterogeneity seen in CBG. The latter is supported by the fact that desialated CBG migrates as two bands in IEF. Migration in IEF is based solely on charge, and since only sialic acid residues are charged in N-linked glycosylation, any heterogeneity seen for the desialated glycoprotein must reside within the protein moiety itself. The presence of O-glycosylation containing an N-acetylgalactosamine with a beta 1-3 linkage to galactose could not be demonstrated using O-glycosidase. N-terminal blockage could not account for the variation, as both the upper and lower variants were able to be sequenced resulting in identical sequences for the first 13 amino acids. The data presented supports the hypothesis that the differences in the sugar as well as the protein moiety are responsible for the heterogeneity seen for CBG.
Steroids 1995 Nov
PMID:Studies on the role of glycosylation in the origin of the electrophoretic variants for rat corticosteroid-binding globulin. 858 98

Mice were immunized with 5-androstene-3 beta-ol-7,17-dione-7-CMO:bovine serum albumin (DHEA-7-O-CMO-BSA) or 5-androstene-3 beta-ol-17-one hemisuccinate-bovine serum albumin (DHEA-3HS-BSA) conjugates and monoclonal antibodies were produced, characterized, and selected for maximum DHEAS binding. Of these hybridomas, four clones from DHEA-3HS-BSA-immunized mice had acceptable criteria for the development of a competitive enzyme-linked immunosorbent assay (ELISA) for DHEAS in plasma. One hybridoma supernatant from DHEA-7-O-CMO-BSA-immunized mice showed 360% cross-reactivity to both androsterone sulfate and epiandrosterone sulfate. This allows the possibility of the direct determination of androsterone sulfate and epiandrosterone sulfate in plasma after correction for the DHEAS contribution. Both ELISAs employ a DHEA-3HS-thyroglobulin conjugate adsorbed to the wells of a standard 96-well microtiter plate. DHEAS in the standards or diluted plasma sample competes with immobilized DHEA-3HS-thyroglobulin for antibody-binding sites. Antibody is detected with anti-mouse-lg peroxidase by further washing, adding o-phenylenediamine substrate, and reading the absorbance at 492 nm. The ELISAs are simple, reproducible, and reliable and, to our knowledge, they are the first tests employing monoclonal antibodies to DHEAS.
Steroids 1996 Dec
PMID:Production and characterization of monoclonal antibodies to dehydroepiandrosterone sulfate: application to direct enzyme-linked immunosorbent assays of dehydroepiandrosterone sulfate and androsterone/epiandrosterone sulfates in plasma. 898 36

A facile and sensitive chemiluminescence enzyme-linked immunosorbent assay (ELISA) of estriol 3-sulfate using a bridge-heterologous system was established. 6 alpha-Hydroxyestriol 3-sulfate 6-hemisuccinate was synthesized as a novel hapten. Antisera were raised in male guinea-pigs against 6 alpha-hydroxyestriol 3-sulfate 6-hemisuccinate-bovine serum albumin (BSA) and 6-oxoestriol 3-sulfate O-carboxymethyloxime-BSA conjugates. Both haptens were coupled to horseradish peroxidase as an enzyme-label reagent. For separation of free and estriol 3-sulfate bound to the antibody, the crude globulin fractions of these antisera were immobilized to CNBr-activated Sepharose-4B. The enzyme activity was measured by chemiluminescent reaction using amino-butylethylisoluminol and hydrogen peroxide as a substrate. The immobilized antibody raised against 6 alpha-hydroxyestriol 3-sulfate 6-hemisuccinate-BSA exhibited a high affinity and an excellent specificity for estriol 3-sulfate. The two bridge-heterologous ELISAs were more sensitive than the homologous systems. The specificity and sensitivity (10 pg) of the bridge-heterologous chemiluminescence ELISAs was comparable to those of the radioimmunoassays (RIAs). Results obtained by the ELISA and the RIA in pregnancy plasmas, showed excellent correlation between ELISA and RIA (r = 0.96).
Steroids 1998 Oct
PMID:Bridge-heterologous chemiluminescence enzyme-linked immunosorbent assay of estriol 3-sulfate in pregnancy plasma. 980 Feb 82

Progesterone (P) is a physiological stimulus of human sperm functions. It is present in high levels at the site of fertilization (cumulus oophorus) and has been described to affect several sperm functions, including motility, capacitation, acrosome reaction, and the ability to bind and to respond to zona proteins. The effects of the steroid are mediated essentially by an increase of intracellular calcium concentrations, stimulation of activity of phospholipases, phosphorylation of proteins, efflux of chloride. These effects are due to activation of a rapid, nongenomic pathway. Whether the effects of progesterone are mediated or not by specific interactions with sperm membrane proteins is questioned. By using an antibody directed against the C-terminal region (P-binding region) of the genomic receptor, we have recently identified two sperm proteins with molecular weights distinct from the classic genomic receptors. In addition, ligand blot analysis with peroxidase-conjugated P demonstrated that P specifically binds these two proteins. Classical ligand binding experiments demonstrated the presence of two specific binding sites with affinity in the nanomolar and in the micromolar range, respectively. The involvement of progesterone in the physiological process leading to fertilization of the oocyte is suggested by several studies. In particular, the demonstration that sperm responsiveness to progesterone is impaired in subfertile patients and that is strictly correlated to the ability of fertilizing the oocyte represents a further indication of the participation of the steroid in this process. In addition, the determination of sperm responsiveness may be predictive of fertilizing ability with a positive predictive value of 90% and can be clinically useful for the preliminary assessment of the male partner to select the appropriate assisted reproductive technique.
Steroids
PMID:Nongenomic progesterone receptor on human spermatozoa: biochemical aspects and clinical implications. 1032 83


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