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1.
Drug Metab Dispos ; 15(5): 618-26, 1987.
Artigo em Inglês | MEDLINE | ID: mdl-2891477

RESUMO

Ketorolac tromethamine (KT), a potent non-narcotic analgesic, with cyclooxygenase inhibitory activity, was administered (14C-labeled and unlabeled) intravenously (iv), orally (po), and intramuscularly (im) in solution to humans, cynomolgus monkeys, rabbits, rats, and mice. KT was absorbed rapidly (Tmax less than 1.0 hr) and efficiently (greater than 87%) following po and im doses in all species. The plasma half-life of ketorolac (K) ranged from 1.1 hr (rabbits) to 6.0 hr (humans). The protein binding of K ranged from 72.0% (mouse) to 99.2% (humans). Linear pharmacokinetics of K was observed in the mouse after single oral doses of KT ranging from 0.25 to 16 mg/kg. Radioactivity was excreted predominantly into urine, ranging from 78.9% (mouse) to 102% (monkey) following iv doses. The dose was excreted into urine primarily as K conjugates, K, and p-hydroxy-K in humans. The monkey was similar to humans with respect to kinetics, but did not form the p-hydroxy metabolite. The rabbit was unusual in that it exhibited substantial presystemic metabolism (50%). The rat excreted a much higher percentage of radioactivity into the feces and formed an additional unidentified metabolite. The most comparable species with respect to humans metabolically was the mouse. The metabolism and excretion of K was similar following iv, po, and im doses within each species studied.


Assuntos
Pirróis/farmacocinética , Tolmetino/farmacocinética , Trometamina/farmacocinética , Administração Oral , Adulto , Animais , Cromatografia Líquida de Alta Pressão , Combinação de Medicamentos/administração & dosagem , Combinação de Medicamentos/farmacocinética , Feminino , Humanos , Injeções Intramusculares , Injeções Intravenosas , Cetorolaco de Trometamina , Macaca fascicularis , Masculino , Camundongos , Coelhos , Ratos , Ratos Endogâmicos , Distribuição Tecidual , Tolmetino/administração & dosagem , Tolmetino/análogos & derivados , Trometamina/administração & dosagem
2.
Endocrinology ; 119(3): 1362-9, 1986 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-3525131

RESUMO

We have previously shown the presence of 17 beta-estradiol in extracts of commercially prepared Saccharomyces cerevisiae ss well as the production of estradiol by yeast grown in the laboratory. In our current study, yeast grown in a chemically defined medium synthesized estradiol in only small amounts, (less than 500 pg/liter). We have analyzed a variety of media commonly used for growing yeast and found that substantial estradiol production (greater than 5 ng/liter) was obtained when yeast were grown in medium supplemented with Bacto-peptone. The peptone was shown to contain significant amounts of estrone, and the results of the experiments establish a precursor-product relationship where estrone from the medium is metabolized to estradiol by S. cerevisiae. Studies with added [3H]estrone demonstrated rapid conversion into [3H]estradiol and a 3H-labeled nonpolar estrogen derivative. The commercially obtained yeast used previously had been grown in a molasses medium. We demonstrate here that the molasses medium contains substantial amounts of estrone and estradiol. We conclude that the conversion of estrone in a culture medium to estradiol in laboratory grown yeast and estrone and estradiol present in the commercially grown yeast medium account for the majority of estradiol found in yeast.


Assuntos
Estrogênios/metabolismo , Saccharomyces cerevisiae/metabolismo , Cromatografia Líquida de Alta Pressão , Meios de Cultura , Estradiol/análise , Estrona/análise , Melaço , Peptonas , Radioimunoensaio , Fatores de Tempo
3.
Prostaglandins Leukot Med ; 16(2): 131-46, 1984 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-6597446

RESUMO

Prostaglandin D2 spontaneously decomposes at physiological pH and temperature to 9-deoxy-delta 9-PGD2 (designated PGJ2). We developed a TLC procedure for the isolation of PGJ2 which was identified by both proton-NMR and mass spectrometry. Freshly prepared PGJ2 was active in inhibiting aggregation induced by ADP in citrated human platelet rich plasma. As reported by Fukushima et al. (1). PGJ2 was less active (x 0.1-0.25) than PGD2 as an inhibitor. Concentrations of PGJ2 that markedly inhibited aggregation of human platelets were generally incapable of inhibiting aggregation of rat or guinea pig platelets. Using a heterologous system of human platelets mixed with guinea pig plasma samples (2), it was shown that the ability of PGJ2 to inhibit platelet aggregation was lost immediately following intravenous injection in anesthetized guinea pigs. This apparent rapid uptake and/or degradation of PGJ2 might also explain why PGJ2 had no effect on blood pressure of anesthetized guinea pigs. PGJ2 was potent in inhibiting proliferation of cultured vascular smooth muscle cells, mouse melanoma cells and mouse fibroblasts. Less potent anti-proliferative effects were seen with two other degradation products of PGD2, one of which was the delta 12 metabolite reported (3,4) to be formed from PGJ2 in a reaction catalyzed by serum albumin.


Assuntos
Prostaglandinas D/análise , Difosfato de Adenosina/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Dinoprostona , Cobaias , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Espectrometria de Massas , Agregação Plaquetária/efeitos dos fármacos , Prostaglandina D2 , Prostaglandinas D/farmacologia , Prostaglandinas E/farmacologia
4.
Proc Natl Acad Sci U S A ; 81(15): 4722-6, 1984 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-6379650

RESUMO

Saccharomyces cerevisiae possesses a high-affinity estrogen binding protein and an endogenous ligand that displaces [3H]estradiol from both the yeast binding protein and mammalian estrogen receptors. Semipurified preparations of this ligand have been shown to exhibit estrogenic activity in mammalian systems. We now describe the purification procedure and ultimate identification of the estrogenic substance in extracts of S. cerevisiae as 17 beta-estradiol. Organic solvent extracts of commercially obtained dried yeast were sequentially chromatographed on silica gel columns and then subjected to a series of reversed phase HPLC fractionations. Active ligand was monitored by [3H]estradiol displacement in a rat uterine cytosol assay. After seven chromatography steps, the purified and highly active ligand exhibited a single peak with retention times identical to those of 17 beta-estradiol on both HPLC and GC. The yeast material was identified as 17 beta-estradiol by its UV absorbance and mass spectrometric fragmentation pattern. In addition, radioimmunoassay confirmed the presence of approximately the same mass of 17 beta-estradiol (approximately equal to 800 ng/1.5 kg of yeast) as estimated both by a competitive binding assay with estrogen receptor and by mass spectrometry. Extraneous contamination by estradiol was excluded by repeat experiments with different batches of starting material and demonstration of estradiol by RIA in conditioned medium and cell pellets of laboratory-grown S. cerevisiae whereas non-conditioned medium did not possess the steroid. We conclude that 17 beta-estradiol is a yeast product.


Assuntos
Estradiol/isolamento & purificação , Saccharomyces cerevisiae/análise , Estradiol/imunologia , Radioimunoensaio
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