Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.3.5.1 (succinate dehydrogenase)
 8,177 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of androgens on the male accessory glands of the rat was assessed in terms of changes in weight and of the specific activity of the mitochondrial enzymes, succinate dehydrogenase, glycerolphosphate dehydrogenase and pyruvate carboxylase, in the epididymis. In some instances, the activity of the cytoplasmic enzymes, hexokinase and phosphofructokinase, was also measured and the influence of androgens on these enzymes was found to be similar to that on the mitochondrial enzymes. After the administration of androgen to castrated rats the specific activity of enzymes reached a new steady state sooner than did epididymal weight. The time taken for the specific activity of the enzymes to reach a new steady state after the removal of androgen was variable, depending on the enzyme and the region of the epididymis. This time was generally longer, however, than the time taken for induction, and in the case of glycerolphosphate dehydrogenase, the decline of activity was slower in the cauda than in the caput. In castrated animals, about 100 times as much androgen was required to attain maximum tissue weight as was required to attain maximum enzyme activity. The epididymis, prostate and seminal vesicles responded similarly to androgen in terms of the dose-response pattern and the time taken for tissue weight to attain a new steady-state value, although the gain in weight of the epididymis relative to its weight in unstimulated control animals was less than the relative gain of the other accessory glands. Enzymes in the cauda epididymidis required lower amounts of androgen to elicit maximum activity than were required by those in the caput. The rate of change in the accessory glands in attaining new steady-state levels of tissue weight and enzyme activity was independent of the dose of androgen except during the first few days of hormone administration. Androgens were the most effective steroids in stimulating an increase of tissue weight and enzyme activity, although some changes were induced by oestradiol-3-benzoate and progesterone.
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PMID:Influence of androgens on the weights of the male accessory reproductive organs and on the activities of mitochondrial enzymes in the epididymis of the rat. 49 85

1. Enzyme activities (units/g wet wt.) were determined in the caput and cauda epididymidis and in epididymal spermatozoa of the rat. 2. The activity of most enzymes in the cauda was between 50 and 100% of that in the caput, except that ATP citrate lyase was barely detectable in the cauda. 3. Spermatozoa, unlike epididymal tissue, contained sorbitol dehydrogenase but lacked ATP citrate lyase. NADP+-malate dehydrogenase, mitochondrial glycerol 3-phosphate dehydrogenase, succinate dehydrogenase, carnitine acetyltransferase and citrate synthase were 5 to 400 times as active in spermatozoa as in epididymal tissue. 4. 2-Oxoglutarate dehydrogenase was the least active member of the tricarboxylic acid cycle in all tissues and most closely matched the measured flux through the cycle. 5. The concentrations of hydroxyacyl-CoA dehydrogenase and carnitine palmitoyltransferase were equivalent to the more active enzymes of the tricarboxylic acid cycle, indicating the capacity for extensive lipid oxidation, and the presence of 3-hydroxybutyrate dehydrogenase suggests that these tissues can also oxidize ketone bodies. 6. Transfer of reducing equivalents from cytoplasm to mitochondrion is unlikely to occur by means of the glycerol phosphate cycle because mitochondrial glycerol 3-phosphate dehydrogenase is relatively inactive in epididymal tissue, whereas the cytoplasmic enzyme has little activity in spermatozoa, but transfer may be accomplished by the malate-aspartate shuttle. 7. Transfer of acetyl units from mitochondrion to cytoplasm could be effected by the pyruvate-malate cycle in the caput of androgen-maintained rats, but not in the other tissues because of the low activity of ATP citrate lyase. Acetyl unit transfer could take place via acetylcarnitine, mediated by carnitine acetyltransferase. 8. Castration resulted in a decrease in the concentration of nearly all enzymes, although subsequent administration of testosterone restored concentrations to values similar to those in animals maintained by endogenous androgen. The extent to which enzyme concentration was changed by an alteration in androgen status was highly variable, but was most marked in the case of pyruvate carboxylase.
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PMID:Activity and androgenic control of enzymes associated with the tricarboxylic acid cycle, lipid oxidation and mitochondrial shuttles in the epididymis and epididymal spermatozoa of the rat. 72 83

The anticancer and immunosuppressive drug cyclophosphamide is extensively used in clinical practice and is known to alter fertility in man. We showed previously that treatment of male rats with low daily doses of cyclophosphamide over a 9-week period caused fetal malformations, a high rate of postimplantation loss and affected epididymal and sperm histology. In the present study, five biochemical measures of epididymal function were used to characterize further the effects of cyclophosphamide on the epididymis. For 1, 3, 6, or 9 weeks, adult Sprague-Dawley rats were gavage-fed daily with saline (control), 5.1 (low dose), or 6.8 (high dose) mg/kg of cyclophosphamide. The specific activities of the two glycolytic enzymes aldolase and lactate dehydrogenase (LDH), the mitochondrial enzyme succinate dehydrogenase, the cytosolic enzyme carnitine acetyltransferase and the lysosomal enzyme acid phosphatase were determined in cytosolic and mitochondrial subcellular fractions from four segments of the epididymis. Cyclophosphamide caused decreases in protein concentrations in all segments of the epididymis only after 6 weeks of treatment with the high dose. The specific activities of aldolase, LDH and succinate dehydrogenase did not differ from control with respect to dose or duration of treatment. In contrast, there were significant effects of cyclophosphamide on carnitine acetyltransferase and acid phosphatase specific activity. After 1 week of treatment, there was a transient dose-related decrease in the specific activity of carnitine acetyltransferase, which was most striking for the corpus epididymidis (76% of control), but which did not differ from control after 3, 6, and 9 weeks. After 6 weeks of treatment with the high dose of cyclophosphamide, carnitine acetyltransferase specific activity in the initial segment and the corpus epididymidis was elevated to 165 and 140%, respectively, as compared with the 1-week high dose values. The specific activity of acid phosphatase did not differ from control after 1 and 9 weeks of treatment. At 3 and 6 weeks, however, there was a dose-related increase in acid phosphatase specific activity for all regions of the epididymis that was most marked in the cauda after the 6-week treatment (140% of control). Therefore, low dose, daily treatment of male rats with cyclophosphamide not only alters specific enzymes in specific segments of the epididymis, but acts in a dose- and time-dependent manner. It is possible that these changes could be mediated by direct, toxic effects of the drug on the epithelium or be secondary to alterations in the spermatozoa as a result of the treatment.
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PMID:Effects of cyclophosphamide on selected cytosolic and mitochondrial enzymes in the epididymis of the rat. 338 43

Effects of alcoholic seed extract of Abrus precatorius Linn. were investigated at a dose of 100 mg/Kg body wt./day/rat for 60 days on fertility, semen profile and sperm metabolism of orally administered sexually mature male albino rats using WHO protocols. Serum testosterone levels were also measured using RIA technique. The data revealed that the cauda epididymal sperm motility was significantly lowered with no effect in its sperm concentration by 60 days of feeding. The scanning electron microscopic study on sperm morphology exhibited decapitation, acrosomal damage and formation of bulges on midpiece region of sperms in treated rats. The biochemical studies on epididymal spermatozoa indicated alterations in their energy and/or oxidative metabolism as evidenced by a fall in succinate dehydrogenase and ATPase levels by extract allocation. It did not exert any effect in body and organ weights. But an average number of implantation sites in females after mating with the treated male rats markedly declined. Contrarily, a significant increase in serum testosterone levels was noted by 60 days of administration. Thus, the decrease in fertility rate in extract receiving animals is correlated with reduced sperm motility, metabolism and altered sperm morphology in epididymis.
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PMID:Antifertility effects of alcoholic seed extract of Abrus precatorius Linn. in male albino rats. 343 10

The three main segments of the elephant epididymis were examined for the occurrence, in the spermatozoa and lining epithelium, of carbohydrates, neutral lipids and phospholipids, ATPase, alkaline phosphatase, succinic dehydrogenase, glucose-6-phosphate dehydrogenase, diaphorases, hydroxysteroid dehydrogenases, acid phosphatase and non-specific esterase. The most distinct feature of the carbohydrate content of the epididymis was a layer of acidic, alcian blue-positive glycoprotein over the luminal surface of the epithelium, particularly in the terminal segment. PAS-positive, diastase-resistant inclusions were also found throughout the epdidymis. Neutral lipid occurred as droplets above and below the nucleus in the epithelium of the middle segment, and as supranuclear accumulations in the terminal segment. All the enzymes except the steroid dehydrogenases were detected in the epididymal epithelium, and all except the steroid dehydrogenases and acid phosphatase were detected in the spermatozoa. There was considerable variation in the intensity of the cytochemical reactions in the epithelium, but not in the spermatozoa, in different regions of the epididymis. In general, the enzymes involved in active transport showed strongest reactions in the initial and terminal segments, the reactions in the stereocilia being the most intense. The enzymes involved in energy metabolism showed strongest reactions in the middle and terminal segments, with the activity being fairly evenly distributed throughout the cytoplasm of the principal cells. However, the two lysosomal enzymes which were studied showed quite different distributions: the reactions for acid phosphatase were strongest in the initial and middle segments, whilst the reactions for non-specific esterase were strongest in the middle and terminal segments. It is suggested that the initial segment is involved in absorptive and anabolic activity, the middle segment in anabolic activity, and the terminal segment (where spermatozoa are stored ready for ejaculation) in considerable metabolic activity and active transport of substrates across the epithelium.
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PMID:Studies of the deferent ducts from the testis of the African elephant, Loxodonta africana. II. Histochemistry of the epididymis. 644 36

The reductive carboxylation of 2-oxoglutarate was found to proceed in mitochondria of rat epididymal fat pads and rabbit perirenal adipose tissue at a rate similar to that in liver mitochondria. In rat fat pads the incorporation of 14C from [5-14C]2-oxoglutarate into fatty acids via the carboxylation was suppressed by butylmalonate by 30%. 2-Oxoglutarate and glutamate stimulated the incorporation into fatty acids of 14C from [2-14C]acetate in rat fat pads with the simultaneous reduction of tissue NADP. These effects persisted after inhibition of succinate dehydrogenase by malonate. It is concluded that in adipose tissue 2-oxoglutarate carboxylation proceeds in both the cytoplasm and mitochondria. Therefore, it can supply carbon atoms as well as NADPH for fatty acid synthesis.
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PMID:Intramitochondrial reductive carboxylation of 2-oxoglutarate in adipose tissue and its contribution to fatty acid synthesis. 653 9

The effects of estradiol benzoate (E2B) at a dose of 50 micrograms/day per rat for 7, 15 and 24 days on some androgenic parameters, viz. organ weights including those of pituitary, succinate dehydrogenase, acid phosphatase, fructose, cholesterol and protein of epididymis, vas deferens, accessory glands and fertility in male rats were investigated. The semen characteristics and standard electron microscopy (SEM) study on sperm morphology of cauda epididymis were also carried out. The results revealed that most of the androgenic parameters were decreased by E2B administration, whereas the accumulation of cholesterol and protein occurred in testis and epididymis due to androgen deprivation to target organs. This deprivation effect also led to a reduction in testicular and cauda epididymal sperm population, loss of motility in the latter and an increase in number of abnormal spermatozoa, thereby manifesting 100% failure in fertility in treated animals. Moreover, these effects were related to the duration of the treatment. Thus, the estradiol benzoate showed androgen antagonistic and antifertility effects in rats.
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PMID:Effect of estradiol benzoate on reproductive organs and fertility in the male rat. 661 37

Histochemical studies have been made of the isocitrate dehydrogenase, succinic dehydrogenase, malate dehydrogenase, glutamate dehydrogenase, DPN diaphorase, TPN diaphorase, delta 5-3 beta-hydroxysteroid dehydrogenase and monoamine oxidase in the caput, corpus and cauda epididymides of normal and alpha chlorohydrin (6.5 mg/kg/9 days) treated rats. Administration of alpha chlorohydrin in a low dose caused a conspicuous decrease in all these enzymes except delta 5-3 beta-HSD, in various cell types of epididymal epithelium and sperms. Biochemical estimations of isocitrate dehydrogenase, succinic dehydrogenase, malate dehydrogenase and delta 5-3 beta-HSD have further supported and confirmed these histochemical observations. These changes in enzyme activities after treatment with low dose of alpha chlorohydrin strongly suggest that TCA cycle and amino acid metabolism of epididymis become defective, much earlier before any histological damage to the epididymis becomes visible.
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PMID:Effects of low doses of alpha chlorohydrin on the dehydrogenases and oxidases of rat epididymal epithelium and sperms: a correlative histochemical and biochemical study. 694 44

The morphology and function of the apical mitochondria-rich cells in the mammalian ductus epididymidis epithelium are revised. These cells are similar in all mammalian species studied. Apical mitochondria-rich cells are scarce (1-5 cells/100 principal cells) and are mainly found in the initial epididymal segments. Their morphology varies from slender cells that extend from the basal lamina to the epididymal lumen, to round cells that protrude into the lumen and are not in contact with the basal lamina. Their cytoplasm is more electron-dense than that of principal cells and contains more mitochondria which, in some species, are surrounded by rough endoplasmic reticulum cisternae. The adluminal cytoplasm displays a few short microvilli and contains many acid phosphatase positive vesicles. Apical mitochondria-rich cells differ from the principal cells in some histochemical features such as: (a) different lectin-staining pattern; (b) more intense reaction to the enzymatic activities: carbonic anhydrase, Ca(2+)-ATPase, peanut-agglutinin-sialidase, NADP dehydrogenase, succinate dehydrogenase, alpha-galactosidase and beta-galactosidase; (c) more intense immunoreaction to several cytokeratin types and to estradiol-related receptor protein; (d) weaker immunoreaction to epithelial membrane antigen and to retinol-binding protein. Although the function of the apical mitochondria-rich cells is still unknown, the following possible functions have been suggested: holocrine secretion; cooperation with the principal cells in epididymal reabsorption of testicular fluid; and acidification of epididymal fluid. Experimental results suggest that differentiation and maintenance of apical mitochondria-rich cells are not under androgen control and that these cells are sensitive to estrogen stimulation.
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PMID:The apical mitochondria-rich cells of the mammalian epididymis. 748 29

Effects of oral administration of mercuric chloride (HgCl2, 1.25 mg/kg) daily for 30 d on the mouse testis, vas deferens, epididymis, and cauda epididymal sperm were investigated. Testis, vas deferens, and epididymis functions were evaluated with respect to sperm count, motility, and viability, and biochemical tests, including succinate dehydrogenase (SDH), adenosine triphosphatase, sialic acid, protein, cholesterol, and glycogen levels in these tissue. Sperm morphology and sperm nuclear integrity were evaluated with standard staining methods. Treatment did not affect whole body and tissue weights. Sperm parameters and fertility were reduced by HgCl2 and most of the biochemical parameters declined. Morphologic histologic alterations were also observed in the tissues studied. All parameters partially recovered after withdrawal of HgCl2 for 45 d.
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PMID:Reversible effects of mercuric chloride on reproductive organs of the male mouse. 891 13


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