Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: DrugBank:APRD00627 (MAP)
 15,705 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The enzymes involved in conversion of pregnenolone to testosterone in Leydig cell tumors showed a wide distribution among smooth endoplasmic reticulum (SER), rough endoplasmic reticulum (RER), and cytosol, while these enzymatic activities in normal testes were associated primarily with smooth endoplasmic reticulum. Progesterone, used as a substrate in the presence of an NADPH-generating system, was metabolized to androstenedione and finally to testosterone by microsomes from some strains of tumor which did not form testosterone from exogenous labeled androstenedione. Treatment of microsomal membranes from normal testes with 0.1 M Ca++ and Mg++ caused a marked decrease in 17 beta-dehydrogenase activity, measured as conversion of exogenous [3H]androstenedione to [3H]-testosterone, without serious effects on activities of 3 beta-ol-dehydrogenase or 17 alpha-hydroxylase. Studies of initial velocity kinetics showed that treatment with magnesium ion resulted in a marked reduction in affinity of androstenedione for 17 beta-dehydrogenase while the maximum velocity was the same as in untreated microsomes. Also, experiments using [14C]progesterone and [3H]androstenedione simultaneously as substrates demonstrated that treatment with Mg++ ion made it more difficult for exogenous [3H]androstenedione to reach the active site of 17 beta-ol-dehydrogenase than [14C]androstenedione formed in the microsomal membrane from [14C]progesterone. Microsomal proteins were more easily solubilized and 3 beta-ol-dehydrogenase was more severely influenced by Mg++ ion in tumor membranes than in normal microsomes.
Endocrinology 1978 Sep
PMID:The possible roles of membrane organization in the activity of androgen biosynthetic enzymes associated with normal or tumorous mouse Leydig cell microsomes. 3 99

The effect of androgen and different progestins on spermatogenesis was studied in young men with subfertility, prostatovesiculitis and haematospermia, and in older men with benign hypertrophy of the prostate. The compounds (testosterone, testosterone oenanthate, ethinyl oestradiol, megestrol acetate, ethinyl norgestrienone and Depo-Provera) were administered intramuscularly, orally or as subcutaneous silastic implants.
J Reprod Fertil Suppl 1976 Sep
PMID:Steroidal compounds (injectable and implants) affecting spermatogenesis in men. 6 50

Cardiovascular responses have been studied in baboons, after total exchange transfusion with hemoglobin solutions having various P50 values. At the end of the exchange transfusion, the hematocrit was 1.5%, the mean hemoglobin concentration was 4.4 g/dl, and the P50 varied between 12 and 26 mm Hg. Cardiac output did not change during the study, although heart rate increased, and stroke volume and MAP decreased. Hemoglobin concentration, per se, does not appear to be the critical stimulus for an increase in cardiac output with hemoglobin solution. In addition, the position of the hemoglobin-oxygen dissociation curve does not appear to influence these hemodynamic responses. The physiological response to anemia in the presence of hemoglobin solution appears different from that observed in the absence of plasma O2 carriers.
Crit Care Med 1979 Sep
PMID:Cardiac output response to extreme hemodilution with hemoglobin solutions of various P50 values. 11 94

The ability of various steroids to induce maturation of Pleurodeles waltlii oocytes after incubation has been studied. Progesterone is metabolized during the course of maturation. All metabolites isolated are less efficient than progesterone for inducing germinal vesicle breakdown. Progesterone binding to the 'melanosome' fraction has been studied (KD = 4.5 X 10(-8) M at 4 degrees C). 20BETA-Hydroxy-pregn-4-en-3-one, the main progesterone metabolite isolated from the oocyte, also binds to the melanosome fraction, but with a lower affinity (KD = 1.6 X 10(-7) M at 4 degrees C). At high concentration 20beta-hydroxy-pregn-4-en-3-one induces maturation, but at low concentration it is a competitive inhibitor of progesterone. Progesterone metabolism in Pleurodeles oocytes can be interpreted as an inactivation process, and also as a mechanism for inhibitime progesterone action.
Mol Cell Endocrinol 1975 Sep
PMID:Mechanism of action of progesterone on amphibian oocytes. A possible biological role for progesterone metabolism. 17 Nov 85

Cholesterol and triglycerides were measured in plasma samples from patient with cancer of the prostate before and after 3 months treatment with either Premarin, Provera, Provera and diethylstilbestrol, or diethylstilbestrol alone. Cholesterol was also measured before and after one of three doses of diethylstilbestrol or placebo. Pretreatment cholesterol levels at 196 +/- 1.3 mg per 100 ml (X +/- SE, N = 1093) were significantly lower than these reported for similar age group noncancer controls. Significant increases occurred with some of the estrogen treatments. Pretreatment cholesterol levels showed a significant negative correlation with age in Stage III and IV patients of both studies and a positive correlation with hemoglobin in Stage III patients of both studies. Pretreatment triglyceride levels at 120 +/- 1.9 mg per 100 ml (X +/- SE, N = 1089) were similar to levels reported for noncancer controls of similar age. Estrogen treatment produced a significant increase in triglyceride levels. Serum triglycerides were significantly correlated with hemoglobin, weight, and cholesterol and negatively correlated with age, Analysis of covariance for both cholesterol and triglycerides showed highly significant treatment effects, but no stage effects and no stage-treatment interactions. It showed that the pretreatment value is of extreme importance for predicting or explaining the 3-month value. Death rates were calculated by level of pretreatment cholesterol or pretreatment triglycerides for all Stage II and IV patients, all treatments combined, and for Study 2 and Study 3 separately. No consistent trends were evident for cholesterol. Spearman correlation coefficients between category of initial triglyceride value and rank of death rate were computed to test for a quadratic effect. When the absolute values of the initial triglyceride values minus the overall mean were correlated with the death rate, a significant negative correlation was found for all causes of death and for deaths due to cardiovascular disease and prostatic cancer. These results indicate that the death rate is highest near the overal mean for initial triglyceride values and decreases as the initial values deviate above or below the mean. Initial triglyceride levels appear to have potential as indicators of risk of death in patients with prostatic cancer. The percentage of patients dead at 1 year by initial triglyceride levels, measured only in Study 3, revealed a pattern similar to that observed for the death rate, that is, the highest percentages were associated with values near the overall mean.
Cancer 1976 Sep
PMID:Response of serum cholesterol and triglycerides to hormone treatment and the relation of pretreatment values to mortality in patients with prostatic cancer. 18 47

Fibrinogen and plasminogen were measured in plasma samples from prostatic cancer patients before and after 3 months of treatment with either Premarin, Provera, Provera and diethylstilbestrol, one of three doses of diethylstilbestrol, or placebo. Plasminogen levels generally were increased significantly with the estrogens but were unchanged following placebo or Provera treatment. Pretreatment plasminogen levels in Study 3 were significantly lower (p less than .001) than in Study 2. Plasminogen pretreatment levels were significantly correlated with age, hemoglobin, body weight, and blood pressure. Fibrinogen pretreatment levels were significantly elevated above normal. They were not significantly with age, hemoglobin, body weight, or blood pressure. Fibrinogen levels generally were significantly decreased by the estrogens. Comparisons of means of pretreatment fibrinogen and plasminogen levels from patients dying during the first year of the study with the mean pretreatment levels of the patient group alive after 1 year on study yielded no significant differences. Death rates were calculated by pretreatment plasminogen or fibrinogen for all treatments of all Stage III and Stage IV patients combined for Study 2 and Study 3 separately. Such rates were calculated for all causes combined and for deaths from prostatic cancer or cardiovascular disease separately. The levels of plasminogen were significnatly negatively correlated with death rate from all causes combined and with cardiovascular disease considered separately, but not with death from prostatic cancer. The levels of fibrinogen were signigicantly positively correlated with death rates from all cuses and nearly significantly with prostatic cancer, but not cardiovascular disease. Elvated pretreatment fibrinogen levels were associated with an increased proportion of deaths at 1 year from all causes and from cancer of the prostate.
Cancer 1976 Sep
PMID:Response of plasma fibrinogen and plasminogen to hormone treatment and the relation of pretreatment values to mortality in patients with prostatic cancer. 18 48

Changes in levels of cyclic adenosine monophosphate (cAMP), prostaglandin F (PGF), progesterone, testosterone, and estradiol-17beta, in preovulatory rat ovaries induced by exogenous luteinizing hormone (LH) have been measured. Ovarian cAMP reached maximal levels 15 min and 1h after LH administration by intravenous and intraperitoneal routes, respectively, and then declined to pre-LH levels by 8 h. Progesterone levels in ovaries and serum rose approximately in parallel with cAMP, but remained elevated throughout the 8-h sampling period. Ovarian testosterone increased to maximal levels 1 h after LH injection, followed by a rapid decline to below pre-LH levels. Ovarian estradiol-17beat concentrations declined steadily throughout the sampling period, reaching almost undetectable levels 8 h after LH treatment. Elevated ovarian PGF levels were observed only at the 4- and 8-h sampling times. Indomethacin treatment, 1 h before LH, prevented the LH-induced increase in ovarian PGF levels, depressed PGF values considerably in saline-injected controls but produced no significant inhibition of ovarian cAMP and progesterone levels. Aminoglutethimide phosphate depressed ovarian concentrations of all three steroids (progesterone, testosterone, and estradiol-17beta) to essentially undetectable levels, both in control and LH-injected rats, but did not alter the LH-induced changes in ovarian cAMP and PGF levels. These observations support the concept of cAMP as a mediator of the LH-induced alterations of ovarian steroidogenesis in vivo during the preovulatory period, but argue against an obligatory role of PGF in this process.
Can J Biochem 1976 Sep
PMID:Effects of indomethacin and aminoglutethimide phosphate in vivo on luteinizing-hormone-induced alterations of cyclic adenosine monophosphate, prostaglandin F, and steroid levels in preovulatory rat ovaries. 18 80

Progesterone causes in goblet cells of oviducts of estrogen hormone-stimulated immature quails selectively gene activation without affecting DNA synthesis. This biological model has been used to study the influence of poly ADP-ribosylation during the processes of DNA transcription. Administration of progesterone in vivo causes an increase of the activity of RNA polymerase I and II in isolated nuclei. This increase is accompanied by a marked decrease of the specific activity of poly (ADP-Rib) polymerase. After in vitro ADP-ribosylation of nuclear proteins the template capacity of chromatin for ""exogenous'' RNA synthesis (with E. coli DNA-dependent RNA polymerases) as well as for ""endogenous'' RNA synthesis with DNA dependent RNA polymerases II is not affected, whereas the data presented seem to indicate that the capacity for RNA synthesis mediated by ""endogenous'' DNA-dependent RNA polymerase I might be inhibited after ADP-ribosylation. Evidence is presented to show that a considerable amount of poly (ADP-Rib), synthesized by poly (ADP-Rib) polymerase in isolated nuclei, is linked with RNA polymerase I. The rate of synthesis of poly (ADP-Rib) is dependent on the incubation temperature (optimum at 25 degrees C) and it can be inhibited by the specific inhibitors of poly (ADP-Rib) polymerase nicotineamide, thymidine and formycin B. Poly (ADP-Rib) is probably associated with RNA polymerase I through a covalent linkage. ADP-ribosylated RNA polymerase I has been purified 550 fold with respect to the nuclear extract corresponding to a 4,000 fold purification from the whole cell homogenate. The ratio between poly (ADP-Rib), formed during preincubation of nuclei with NAD, and RNA polymerase I remains almost constant during the purification procedures. The extent of ADP-ribosylation of RNA polymerase I decreases during gene expression. Thus we conclude that poly ADP-ribosylation of this enzyme is one of the regulatory mechanisms by which specificity of DNA transcription is achieved.
Mol Cell Biochem 1976 Sep 30
PMID:Poly ADP-ribosylation of DNA-dependent RNA polymerase I from quail oviduct. Dependence on progesterone stimulation. 18 9

The effects of progesterone on some of the hepatic enzymes associated with lipogenesis and gluconeogenesis in rats is presented. Progesterone was given, 1.25 mg, twice daily, for 14 days followed by 2.5 mg twice daily for 7 days. Animals were killed after 21 days of treatment. Enzymes studied included phosphofructokinase (PFK) malic enzyme (ME), glucose-6-phosphate dehydrogenase (G-6-PD), citrate cleavage enzyme (CCE), glycerol-3-phosphatee dehydrogenase (g-3-PD), fatty acid synthetase (FAS), pyruvate carboxylase (PC), phosphenolpyruvate carboxykinase (PEPCK), fructose-1,6-diphosphatase (FDPase), and lactate dehydrogenase (LDH). PFK, ME, G-6-PD, and CCE were elevated significantly after progesterone administration, while FAS and G-3-PD were unchanged. These changes may represent insulin effects. Progesterone treatment also results in increased PEPCK. This enzyme is associated with control of gluconeogenesis. PEPCK is considered to be a key rat-limiting enzyme in the "dicarboxylic acid shuttle." This finding may indicate an increased capability for glycogen formation.
Am J Obstet Gynecol 1977 Sep 15
PMID:Effects of progesterone on some enzymes of fat and carbohydrate metabolism in rat liver. 19 50

18- and 11beta-Hydroxylation of deoxycorticosterone and side chain cleavage of cholesterol were studied in mitochondria and submitochondrial reconstituted systems prepared from rat and bovine adrenals. A mass fragmentographic technique was used that allows determination of hydroxylation of both exogenous and endogenous cholesterol. The following results were obtained. (1) Treatment of rats with excess potassium chloride in drinking fluid increased mitochondrial cytochrome P-450 as well as 18- and 11beta-hydroxylase activity in the adrenals. Cholesterol side chain cleavage was not affected. In the presence of excess adrenodoxin and adrenodoxin reductase, cytochrome P-450 isolated from potassium chloride-treated rats had higher 18- and 11beta-hydroxylase activity per nmol than cytochrome P-450 isolated from control rats. The stimulatory effects on 18- and 11beta-hydroxylation were of similar magnitude. (2) Long-term treatment with ACTH increased cholesterol side chain cleavage in the adrenals but had no effect on 18- and 11beta-hydroxylase activity. The amount of cytochrome P-450 in the adrenals was not affected by the treatment. It was shown with isolated mitochondrial cytochrome P-450 in the presence of excess adrenodoxin and adrenodoxin reductase that the effect of ACTH was due to increase of side chain cleavage activity per nmol cytochrome P-450. Side chain cleavage of exogenous cholesterol was affected more than that of endogenous cholesterol. (3) Gel chromatography of soluble cytochrome P-450 prepared from rat and bovine adrenal mitochondria yielded chromatographic fractions having either a high 18- and 11beta-hydroxylase activity and a low cholesterol side chain cleavage activity or the reverse. The ratio between 18- and 11beta-hydroxylase activity was approximately constant, provided the origin of cytochrome P-450 was the same. (4) Addition of progesterone to incubations of deoxycorticosterone with soluble or insoluble rat adrenal cytochrome P-450 competitively inhibited 18- and 11beta-hydroxylation of deoxycorticosterone to the same degree. Addition of deoxycorticosterone competitively inhibited 11beta-hydroxylation of progesterone with the same system. Progesterone was not 18-hydroxylated by the system. From the results obtained, it is concluded that 18- and 11beta-hydroxylation have similar properties and that the binding site for deoxycorticosterone is similar or identical in the two hydroxylations. The possibility that the same specific type of cytochrome P-450 is responsible for both 18- and 11beta-hydroxylation of deoxycorticosterone is discussed.
J Lipid Res 1977 Sep
PMID:Common characteristics of the cytochrome P-450 system involved in 18- and 11 beta-hydroxylation of deoxycorticosterone in rat adrenals. 19 3


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