The Allen-Doisy test for estrogens reinvestigated.
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Lymphocyte migration was studied at three stages of rat pregnancy by the tracer sample principle of injecting syngeneic thoracic duct lymphocytes labelled with chromium-51 (for organ counting) or [3H]leucine (for autoradiography). Except for one abnormal embryo no entry of lymphocytes into the foetus was detected. There was a small localization of lymphocytes in the placenta which did not differ significantly between allogeneic or syngeneic mating. Pregnancy produced little or no alteration of lymphocyte traffic into the spleen or lymph nodes, including those draining the uterus. The administration of oestrogens to virgin rats increased the height of the specialized endothelium lining the post-capillary venules in the mesenteric lymph nodes but had no effect on lymphocyte traffic.
In mature female and male rats sex hormone deficiency was produced by surgical castration and by antiestrogen or antiandrogen administration. For the latter purpose we used the nonsteroidal antiestrogens tamoxifen, keoxifene (LY156758) and tetramethylhexestrol, and the steroidal antiandrogen cyproterone acetate. Dosages of 0.4 mg tamoxifen/rat/day and isomolar dosages of keoxifene and tetramethylhexestrol led to a bone mass reduction which was comparable to ovariectomized rats. Cyproterone acetate showed, at 10 mg/rat/day, a similar decrease in bone mass like orchidectomy. The often discussed intrinsic estrogen activity of the antiestrogens was present only in the highest dosage tested of tamoxifen. Keoxifene and tetramethylhexestrol showed no estrogenic effects, but this may be a dosage problem. Cyproterone acetate revealed no androgenic side-effects. These results indicate that antigonadal hormone drugs reduce bone mass to a varying extent.
After ovariectomy DMBA tumor-bearing SD rats were treated with the estrogen DES, a combination of DES plus mammary tumor-inhibiting antiestrogen (tetramethylHES, 3,3'HES and tamoxifen respectively) or with tetramethylHES alone. Small doses of DES led to a stimulation of tumor growth showing a maximum effect at 1 microgram/kg/day, whereas higher doses inhibited tumor growth. In the combination experiment only tetramethylHES reduced, i.e. antagonized, the DES effect. Tamoxifen and 3,3'HES, however, led to an increase of the tumor growth-stimulating and inhibiting effects of DES. Only the dose of 10 mg/kg/day of tetramethylHES led to a slight stimulation of the tumor growth in ovariectomized DMBA tumor-bearing rats. These results indicate that 3,3'HES and tamoxifen possibly unfold their mammary tumor-inhibiting activity by means of their estrogenic potency, whereas tetramethylHES might act as an antiestrogen, though the latter compound does not lack estrogenic activity completely.
Two groups, each of ten female rats, were orally dosed with the synthetic oestrogens diethylstilboestrol (DES; 6 mg/kg day) and hexoestrol (60 mg/kg/day) for 6 wk. A further group of ten animals received clomiphene citrate (2 mg/kg/day) and DES (6 mg/kg/day), while two groups, each of ten animals, acted as controls. One animal treated with DES died within the 42-day study period. Its death was associated with a bleeding disorder related to severe liver damage. The remaining treated animals showed little overt toxicity. The major haematological finding in the treated animals that survived was a moderate, stable, normocytic, normochromic anaemia. The terminal bone marrows of these animals showed a modest degree of erythroid hypoplasia. There were stimulatory and other changes in the reproductive tract and there were gains in the liver, adrenal and pituitary weights. These effects were more marked in the rats treated with hexoestrol, the gains in the relative organ weights being particularly striking: liver, 51%, adrenals, 210%, uterus, 79% and pituitary, 500%. The oestrogens caused reductions in body weight (18% in both cases) and appetite, a modest degree of fatty change in the liver, and alterations in the serum proteins. The Thrombotest clotting times of the hexoestrol-treated rats were prolonged. Clomiphene citrate decreased the adverse effects of DES on appetite and body weight, and sharply decreased the gains in the pituitary and uterine weights from 243 to 80% and 59 to 14%, respectively. The toxic effects of the oestrogens in the rat were more closely related to the dose administered than to their hormonal potency. Oestrogens are less toxic to the rat than they are to the cat, dog and ferret, and the toxic effects are in many respects qualitatively different.
The synthetic oestrogen hexoestrol, administered at 60 mg/kg/day for 4 days to female rats in 3 studies, caused the following mean changes in the relative weights of some of the principal organs: liver (+37%), spleen (-11%), adrenals (+43%), kidneys (+3%), pituitary (+23%), uterus (+49%), and ovaries (+13%). The heart weights showed no consistent changes. The mean relative organ weights of hypophysectomized, hexoestrol-treated rats did not differ significantly from those of untreated hypophysectomized controls. The latter animals had lower organ weights than sham-operated controls. Pretreatment with clomiphene citrate at dose levels of 20-60 mg/kg/day prevented in a dose-dependent manner most of the organ weight changes induced by hexoestrol. The exception was the adrenal weight, which was increased. Compared with controls, the mean relative organ weights of rats receiving clomiphene alone at 60 mg/kg/day differed as follows: liver (-18%), spleen (-17%), heart (-16%), adrenals (+7%), kidneys (-11%), pituitary (-13%), uterus (-25%), and ovaries (-4%). The changes affecting the liver, spleen, heart, kidneys and uterus were significant. Rats immunised with a monkey antiserum to rat growth hormone and treated with hexoestrol had significantly lower relative liver weights than did animals treated with hexoestrol alone. No other significant differences were observed. It is tentatively concluded that there is a mediating or co-operative pituitary influence involved in the significant hepatic, uterine and adrenal weight gains caused by hexoestrol. Clomiphene may act centrally to affect these organ weight changes and, indeed, may act at this level to (mainly) anti-organotrophic effect even in the absence of exogenous oestrogen. In the case of the hexoestrol-induced liver enlargement, the role of pituitary growth hormone is worth further investigation.
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Our approach to develop platinum complexes with a selective effect on the hormone-dependent MC by exchanging the two NH3 groups of cisplatin by an 1,2-bis(4-hydroxy-phenyl)ethylenediamine derivative which possesses estrogenic activity, was successful. The most interesting compound of this new platinum complex series, meso-(1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamine)dichloroplati num(II) (meso-1-PtCl2) and its water soluble sulfatoplatinum(II) derivative (meso-1-PtSO4) were significantly more active on the DMBA-MC and the receptor positive MXT-MC than cisplatin and the related ligand 1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamine (meso-1). According to our proposed mechanism of action, meso-1-PtX (X = Cl2 or SO4) should be enriched in the nuclei of mammary tumor cells, which possess an intact ER system (i.e. an intact cytoplasma nucleus translocation process), thereby causing very strong tumor growth inhibition. Preliminary studies of meso-1-PtSO4 on the DMBA-MC confirm this assumption. In the tumor tissue we found higher Pt-levels than in uterine tissue, which also contains ERs. The Pt-levels of the tumor tissue are much higher than those of skeletal muscle and of blood. In therapeutic dosages meso-1-PtSO4 does not cause kidney damages in rats.
A competitive enzyme-linked immunosorbent assay (ELISA) was developed for the quantitative detection of the hexoestrol (HES). Polyclonal rabbit antisera, raised against protein conjugate hexoestrol-mono-carboxyl-propyl-ethyl-bovine-serum-albumin (HES-MCPE-BSA), were utilized in immobilized antibody-based and competitive immunoassays. Assay conditions, including concentrations of antisera and Horseradish peroxidase (HRP)-HES were optimized. The effect of incubation time, surfactant concentration, ionic strength and pH of the medium were also investigated. The typical calibration curve gave an average IC50 value of 2.4 ng/ml, calibration range from 0.2 ng/ml to 30.5 ng/ml and a detection limit of 0.07 ng/ml. The specificity of the assay was tested against HES structurally related compounds, and the assay proved highly selective for HES. Assay performance was validated by using spiked pork and liver tissues samples. Moreover, it was compared with liquid chromatography-tandem mass spectrometry. The ion pair for quantification of HES was 269.4/134, and linear equation of HES was Y=0.2148X-0.0374 (r=0.9993). The two analytical methods can be applied to monitor HES and other steroid residues in edible foods.
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BACKGROUND & AIMS: 4,4'-Diethylaminoethoxyhexestrol (DEAEH), amiodarone, and perhexiline cause steatohepatitis in humans. The mechanisms of these effects are unknown for DEAEH and have not been completely elucidated for amiodarone and perhexiline. The aim of this study was to determine these mechanisms. METHODS: Rat liver mitochondria, cultured rat hepatocytes, or rats were treated with these drugs, and the effects on mitochondrial respiration, beta-oxidation, reactive oxygen species formation, and lipid peroxidation were determined. RESULTS: DEAEH accumulated in mitochondria and inhibited carnitine palmitoyl transferase I and acyl-coenzyme A dehydrogenases; it decreased beta-oxidation and caused lipid deposits in hepatocytes. DEAEH also inhibited mitochondrial respiration and decreased adenosine triphosphate (ATP) levels in hepatocytes. DEAEH, amiodarone, and perhexiline augmented the mitochondrial formation of reactive oxygen species and caused lipid peroxidation in rats. CONCLUSIONS: Like amiodarone and perhexiline, DEAEH accumulates in mitochondria, where it inhibits both beta-oxidation (causing steatosis) and respiration. Inhibition of respiration decreases ATP and also increases the mitochondrial formation of reactive oxygen species. The latter oxidize fat deposits, causing lipid peroxidation. We suggest that ATP depletion and lipid peroxidation may cause cell death and that lipid peroxidation products may account, in part, for other steatohepatitis lesions.
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The combination of supercritical-fluid extraction-supercritical-fluid chromatography-tandem mass spectrometry has been evaluated for the detection of residues of a small group of veterinary drugs in freeze-dried pig's kidney. During extraction with supercritical CO2 the drugs were retained by the column while non-polar endogenous material was not retained and thus passed to waste. Subsequent changes to the mobile phase composition eluted the drugs which were detected with high specificity by tandem mass spectrometry. Although the sensitivity in this preliminary study was not adequate for surveillance or enforcement, there is potential for further development of the approach.
A number of chronic hepatic lesions can result from adverse reactions to medicinal agents. Such lesions include a form of chronic active hepatitis; hepatic steatosis, phoepholipidosis and granulomatosis; several vascular lesions; two types of noncirrhotic portal hypertension; several types of cirrhosis and several neoplasms.
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