The activity of some intracellular oxidative enzymes in the thyroid follicular epithelium of Xenopus laevis Daud. in experimental long-term hypokinesia.

Histoenzymological methods were applied to examine the activities of previously little studied intracellular oxidative enzymes in the cells of the thyroid follicular epithelium of Xenopus laevis Daud. specimens kept in aquarium. Succinate, lactate, alpha-glycerophosphate, glucose-6-phosphate and reduced NAD and NADP dehydrogenases and cytochrome oxidase were studied. In comparison with other chordate species a very strong activity was revealed particularly by lactate dehydrogenase. The data obtained suggest that the metabolism in thyroid cells of the motionless Xenopus is based on glycolysis mainly.     

Oxidative enzymes in the sebaceous glands of the domestic cat

Synopsis The distribution and activities of several oxidative enzymes in various regions of the sebaceous glands of the domestic cat have been studied. The results obtained emphasize the outstanding importance of NADP-linked dehydrogenases for lipogenesis during sebum production. In particular, the reactions for glucose-6-phosphate dehydrogenase were very strong. Among the NAD-linked dehydrogenases investigated, lactate dehydrogenase showed strong activity in the peripheral cells of the sebaceous gland. The reactions for cytochrome oxidase and succinate dehydrogenase were weaker.     

Localization of some steroidogenic enzymes in the ovary of the rabbit

The distribution of delta 5-3 beta-HSD, peroxidase and cytochrome oxidase in immature, sexually mature and pregnant rabbit ovary has been studied histochemically. Corpora lutea are found only in pregnant rabbits. delta 5-3 beta-HSD is present in the theca interna of mature follicles, corpora lutea and interstitial gland cells but is absent in the granulosa cells of both developing and mature follicles. The granulosa cells of mature and developing follicles, hypertrophied theca interna and the luteal cells all show intense cytochrome oxidase activity. Peroxidase is present in the corpora lutea only. It is suggested that delta 5-3 beta-HSD in the theca interna and interstitial gland cells is the enzyme responsible for steroid synthesis in the ovaries of immature as well as sexually mature rabbits, while peroxidase and delta 5-3 beta-HSD present in the corpora lutea together regulate luteal steroidogenesis during pregnancy. The intense cytochrome oxidase activity together with peroxidase and delta 5-3 beta-HSD confirms the observations that this tissue is a site of intense oxidative activity.     

近交系剑尾鱼的遗传生化标记研究

目的通过研究对RR-B、RW-H、BY-F三个近交系和非选育剑尾鱼的研究比较,建立近交系剑尾鱼的遗传生化标记检测技术。方法依照国标GB／T14927.1-2008的遗传操作规程优化实验条件,对三个近交品系及非选育群剑尾鱼的不同组织的6个遗传生化位点进行研究,以得到其遗传生化图谱。结果在6个生化位点中,同一品系剑尾鱼同工酶存在组织特异性,多数同工酶在肝中活性较强。同一生化位点在不同品系间存在差异。RR-B系在葡萄糖磷酸异构酶（Gpi）、6-磷酸葡萄糖脱氢酶（Gpd）位点表现出特异性条带,RW-H系在过氧化氢酶（Ce）位点表现出特异性条带。同一生化位点在各品系内表现较为一致,而在非选育剑尾鱼中在上述三个生化位点表现出多态性。在酯酶（ES）、碱性磷酸酶（AKP）、乳酸脱氢酶（LDH）位点,各品系谱带不易区分其差异。结论建立了剑尾鱼近交系生化标记检测技术,可望用于近交系剑尾鱼的遗传质量监测。     

剑尾鱼线粒体细胞色素b基因的序列分析

目的　克隆和测定剑尾鱼 (Xiphophorushelleri)线粒体细胞色素b基因 (cytb)的全序列。方法　提取剑尾鱼肝脏的总DNA。设计合成特异引物进行PCR扩增。扩增产物经琼脂糖电泳检测、纯化后克隆到pGEM Teasyvectorsystem中的T载体上 ,筛选转化子 ,提取质粒 ,酶切鉴定。挑取重组质粒pGEM T xhcytb 11进行序列测定。结果　获得了剑尾鱼线粒体cytb基因的全序列 ,共 114 0bp。结论　用BLAST与GenBank中的线粒体DNA序列进行比较 ,显示剑尾鱼与其他鱼类的cytb基因具有较高的同源性 ;根据剑尾鱼与其他 13种鱼的cytb基因序列同源性所建立的进化树 ,与传统的分类地位基本吻合     

Perturbations in carbohydrate metabolism during cypermethrin toxicity in fish, Tilapia mossambica

Sublethal concentrations (0.04 ppm) of cypermethrin induced significant metabolic changes in brain, liver and gill tissues of fish, T. mossambica. While cypermethrin caused depletion in glycogen and pyruvate levels lactate content was elevated in all the tissues. While phosphorylase 'a' and aldolase activity increased, phosphorylase 'b' activity registered a decrease in the present study. A decrease in lactate dehydrogenase activity with increase in lactate levels suggests reduced mobilization of pyruvate into citric acid cycle. Glucose-6-phosphate dehydrogenase activity was also elevated indicating enhanced oxidation through HMP pathway during cypermethrin toxicity. Inhibition of succinate, malate and isocitrate dehydrogenases and cytochrome c oxidase activity indicates impaired oxidation of carbohydrates through citric acid cycle.     

Acetylcholine esterase sensitivity to chronic administration of diphenylhydantoin and effects on cerebral enzymatic activities related to energy metabolism

The effect of chronic treatment (8 months) with diphenylhydantoin (DPH) on rat brain was studied. The activity of some enzymes related to energy transduction (lactate dehydrogenase, citrate synthase, and malate dehydrogenase; NADH-cytochromec reductase and cytochrome oxidase) and neurotransmission (acetylcholine esterase) was evaluated both in the whole brain homogenate and/or in the crude mitochondrial fraction. A clear-cut decrease of acetylcholine esterase activity was observed, the decrease continuing even after treatment was discontinued. Effects on energy metabolism and on lactate dehydrogenase, malate dehydrogenase, and cytochrome oxidase are discussed.     

Correlation between the activity of enzymes involved in energy and carbohydrate metabolism with the size and weight parameters of some coregonidae and salmonidae fish

The correlation between the energy and carbohydrate metabolism rate with the length and weight of salmon (Salmo salar L.) and whitefish (Coregonus lavaretus L., Coregonus albula L.) studied in nature and farmed rainbow trout (Parasalmo mykiss Walb.) has been investigated. The results of the study show that the largest and fastest growing fish had high activity of enzymes involved in aerobic energy metabolism (cytochrome c oxidase and malate dehydrogenase) and anaerobic metabolism (lactate dehydrogenase in muscles and 1-glycerophosphate dehydrogenase and glucose-6-phosphate dehydrogenase in liver). Age-related changes of the investigated parameters are caused by a general reduction of the aerobic metabolism rate and oxygen consumption during ontogenesis, increased lipid metabolism, and the amount of stored substances. It is also shown that pubescent male and female whitefish (4+ and 5+) have differences in the correlation between enzyme activity of cytochrome c oxidase, 1-glycerophosphate and glucose-6-phosphate dehydrogenases and the length and weight of individuals.     

The in vivo effects of tetrahydrocannabinol on the activity of lactate and succinate dehydrogenases in rat preovulatory follicles

Summary The effects of ⁹-tetrahydrocannabinol on the activities of lactate and succinate dehydrogenases in the theca interna and membrana granulosa of rat preovulatory follicles have been analysed microdensitometrically using the same injection regime employed in a previous study on steroidogenic enzymes. A small but statistically significant (18%) decrease in succinate dehydrogenase activity was observed in the theca interna, but none in any region of the membrana granulosa. Lactate dehydrogenase activity was unaffected by THC administration. Thus, a dosage and regimen sufficient to cause significant decreases in the activities of steroidogenic enzymes had little effect on succinate and lactate dehydrogenases in rat preovulatory follicles.     

Membrane-bound respiratory of Spirillum itersonii.

The membrane-bound respiratory system of the gram-negative bacterium Spirillum itersonii was investigated. It contains cytochromes b (558), c (550), and o (558) and beta-dihydro-nicotinamide adenine dinucleotide (NADH) and succinate oxidase activities under all growth conditions. It is also capable of producing D-lactate and alpha-glycerophosphate dehydrogenases when grown with lactate or glycerol as sole carbon source. Membrane-bound malate dehydrogenase was not detectable under any conditions, although there is high activity of soluble nicotinamide adenine dinucleotide: malate dehydrogenase. When grown with oxygen as the sole terminal electron acceptor, approximately 60% of the total b-type cytochrome is present as cytochrome o, whereas only 40% is present as cytochrome o in cells grown with nitrate in the presence of oxygen. Both NADH and succinate oxidase are inhibited by azide, cyanide, antimycin A, and 2-n-heptyl-4-hydroxyquinoline-N-oxidase at low concentrations. The ability of these inhibitors to completely inhibit oxidase activity at low concentrations and their effects upon the aerobic steady-state reduction levels of b- and c-type cytochromes as well as the aerobic steady-state reduction levels obtained with NADH, succinate, and ascorbate-dichlorophenolindophenol suggest that presence of an unbranched respiratory chain in S. itersonii with the order ubiquinone leads to b leads to c leads to c leads to oxygen.     

Enzymic markers of thyroid C cells in some rodents.

The paper provides comparative data of the localization of histochemical reactions demonstrating the activities of alpha-glycerophosphate and succinate dehydrogenases, acid phosphatase, non-specific esterases and non-specific acetylcholinesterase in the C cells of thyroids of 26 animals belonging to 5 rodent species. The family Muridae is represented by the Wistar albino rat and albino mouse, the family Microtidae by the bank vole Clethrionomys glareolus (Schreber 1780), the field vole Microtus agrestis L. 1761, and the pine vole Pitymys subterraneus De Selys-Longchamps 1825. The observed enzyme activity differences were most conspicuous on comparing the rat and mouse thyroids and in a much less degree the Microtidae thyroids. Among the histochemical reactions tested that for succinate dehydrogenase proved to be least effective as a C cell marker, alpha-glycerophosphate dehydrogenase being better, and acid phosphatase and non-specific esterases the best (not in the rat thyroid). The reaction for non-specific cholinesterase (with some limitations) gave satisfactory results in the C cells of all animal's thyroids. The present paper continues earlier studies [19] on the morphology of the C cells in thyroid glands of the rodents of the families Muridae and Microtidae and aims at supplementing them with histochemical data of enzymic activities. It deals with enzyme reactions that are employed as C cell markers in Mammals other than Rodents.     

Enzymologic study of the structural organization of the matrix or rat liver peroxisomes]

The effect of ionic strength and pH on the release of some enzymes of the matrix of peroxisomes in rat's liver was studied. Catalase, L ALpha-hydroxy acid oxidase, isocitrate dehydrogenase, glycerophosphate dehydrogenase and lactate dehydrogenase were easily released from the particles during their lysis and treatment with 0.16 M KCl, whereas urate oxidase, NADH cytochrome c reductase and D-amino acid oxidase were not solubilized. After the solubilization of peroxisomal membrane by 0.2% Triton X-100, the remaining core contained about 50% amino acid oxidase activity, and had 1.28--1.30 g/cm3 density. These results suggest that D-amino acid oxidase associates with urate oxidase in the peroxisomal core.     

The effect of phenolic compounds on the activity of respiratory chain enzymes and on respiration and phosphorylation activities of potato tuber mitochondria

The effect of derivatives of benzoic and cinnamic acids, quereetin,p-benzoquinone, and 2,5-dimethylbenzoquinone on oxygen consumption mitoehondrial suspensions and on the activity of some respiratory chain enzymes was studied. Benzoquinone and 2,5-dimethylbenzoquinone highly significantly inhibited the respiration and phosphorylation rates and malate- and succinate dehydrogenase activities. Chlorogenic acid, similarly as the quinones, very significantly inhibited the activities of the studied dehydrogenases but did not affect cytochrome oxidase. Oxygen consumption by intact mitochondria was not inhibited, only the oxidativo phosphorylation was significantly uncoupled. Quereetin significantly enhanced dehydrogenase activities and completely inhibited cytochrome oxidase activity. The respiration and phosphorylation activities of the mitochondria were significantly inhibited by quereetin. The effect of the other phenolic compounds studied on respiration and phosphorylation activities was not significant. Succinate dehydrogenase activity was the most affected enzyme among the respiratory chain enzymes. It was significantly inhibited by all the above phenolic compounds at 1^-4M or 5 10^-5M concentrations with the exception of gallic acid.     

Enzymatic coordination indices of leukocytes in the prognosis of mouse resistance to staphylococcal toxin

The activity of succinate, lactate and alpha-glycerophosphate dehydrogenases, as well as acid phosphatase, in the lymphocytes and neutrophils of the blood was studied in noninbred white mice prior to the intraperitoneal injection of 1 LD50 of staphylococcal toxin. As the result of intoxication, a half of the animals died and the other half survived. The two groups of the animals differed in the levels of the activity of succinate dehydrogenase and hyaloplasmatic alpha-glycerophosphate dehydrogenase in the neutrophils and lymphocytes, and also differed in the stability of correlations between the activity of succinate and lactate dehydrogenases in the lymphocytes and neutrophils and, besides, between the activity of lactate dehydrogenase in these types of cells.     

Comparison of Effects of Sublethal Microwave Radiation and Conventional Heating on the Metabolic Activity of Staphylococcus aureus

This study was conducted in an attempt to characterize some of the effects of sublethal microwave radiation on cells of Staphylococcus aureus. Cultures were exposed to microwave radiation for 10, 20, 30, and 40 s. The effects of a conventional heat treatment were also compared by placing flasks containing cultures in a boiling water bath for the amount of time required to reach temperatures equivalent to those found in cultures exposed to microwave radiation. Control, microwave-treated, and conventionally heat-treated cultures were centrifuged, pellets were resuspended in distilled water, and the resulting suspensions were passed through a French pressure cell. Cell lysates and walls were then isolated and assayed for enzymatic activity. Thermonuclease production was also determined at various levels of exposure of cells to microwave radiation. Activities of malate and α-ketoglutarate dehydrogenases, cytochrome oxidase, and cytoplasmic adenosine triphosphatase were higher in microwave-treated cells than in control cells. Membrane adenosine triphosphatase, alkaline phosphatase, and lactate dehydrogenase activities were unaffected when cells were exposed to microwave radiation. The activity of glucose-6-phosphate dehydrogenase was decreased by exposure of cells to microwave radiation. In conventionally heated cells, activities of glucose-6-phosphate and malate dehydrogenases and cytoplasmic adenosine triphosphatase increased activities of α-ketoglutarate and lactate dehydrogenases decreased, and alkaline phosphatase activity remained unaffected. Increased levels of thermonuclease activity were observed when cells were exposed to microwave radiation for 10 or 20 s. Data indicate that microwave radiation affects S. aureus in a manner which cannot be explained solely by thermal effects.     

Larger swordtail females prefer asymmetrical males

Many organisms, including humans, find symmetry more attractive than asymmetry. Is this bias towards symmetry simply a by-product of their detection system? We examined female preference for symmetry of the pigment pattern vertical bars in the swordtail fishes Xiphophorus cortezi and Xiphophorus malinche. We found a relationship between preference for symmetry and female size, with larger and thus older females spending significantly more time with the asymmetrical video animation as compared to the symmetrical video animation. The preference for asymmetry we report demonstrates that even if females can detect symmetrical males better, this does not preclude subsequent selection on females to prefer symmetrical or asymmetrical males. In addition, because the preference was correlated with female size, past studies may have missed preference for either asymmetry and/or symmetry by not examining the relationship between female preference and size/age or by measuring a limited size/age distribution of females. In both of the species of swordtail fishes examined, a high proportion of males are asymmetrical by more than one bar. We suggest that female preference may be maintaining fluctuating asymmetries in these fishes.     

Effect of boseimycin on some enzyme systems ofBacillus subtilis

The effect of boseimycin on the in vitro activity and in vivo synthesis of alkaline phosphatase, aconitase and lactate, isocitrate, glutamate and alanine dehydrogenases was studied in Bacillus subtilis. At a subinhibitory concentration, synthesis of glutamate dehydrogenase was stimulated but alkaline phosphatase, lactate dehydrogenase and aconitase synthesis was inhibited. On the contrary, boseimycin inhibited slightly the activity of lactate dehydrogenase in cell-free extracts. Glutamate dehydrogenase and aconitase activities were not affected.     

Stimulation of NADH oxidation by xanthine oxidase and polyvanadate in presence of some dehydrogenases and flavin compounds

The rates of NADH oxidation in presence of xanthine oxidase increase to a small and variable extent on addition of high concentrations of lactate dehydrogenase and other dehydrogenases. This heat stable activity is similar to polyvanadate-stimulation with respect to pH profile and SOD sensitivity. Isocitric dehydrogenase (NADP-specific) showed heat labile, SOD-sensitive polyvanadate-stimulated NADH oxidation activity. Polyvanadate-stimulated SOD-sensitive NADH oxidation was also found to occur with riboflavin, FMN and FAD in presence of a non-specific protein, BSA, suggesting that some flavoproteins may possess this activity.     

Histochemical observations on the exoerythrocytic malaria parasite Plasmodium berghei in rat liver

Enzyme histochemical methods were performed on sporozoite infected liver tissue of rats in order to gain insight into the nutrition and metabolism of exoerythrocytic forms of Plasmodium berghei. The following enzymes were demonstrated in the hepatocytic stages of the parasites, obtained 41 and 48 h after inoculation of sporozoites: acid phosphatase, cytochrome oxidase, NADH-tetrazolium reductase, succinate dehydrogenase, NAD+ and NADP+ dependent isocitrate dehydrogenase, NADP+-dependent malate dehydrogenase, lactate dehydrogenases, 6-phosphogluconate dehydrogenase and glucose-6-phosphate dehydrogenases and alpha-glycerol-phosphate dehydrogenase. The results suggest that a conventional Embden-Meyerhoff pathway, pentose phosphate pathway and Krebs' citric acid cycle may in part be present in these exoerythrocytic parasites. Alkaline phosphatase, nucleoside polyphosphatase, 5' nucleotidase, glucose-6-phosphatase, alpha-glucan phosphorylase, NAD+ dependent malate dehydrogenase, amino-peptidase M and non-specific esterases were not detected by our techniques in the parasite. The enzyme distribution of this intrahepatocytic malaria parasite revealed by histochemistry is compared with the enzyme distribution in the other phases of the parasite's life cycle.     

Histochemical studies of some enzymes in the tissues of the schistosome vector snailBulinus truncatus (Audouin) with special reference to the effects of a molluscicide. I. Dehydrogenases

Summary The histochemistry of five dehydrogenases, namely isocitrate, succinate and lactate dehydrogenases and NADH and NADPH diaphorases were studied in the tissues of the schistosome vector snail,Bulinus truncatus, before and after treatment with the molluscicide Frescon. Isocitrate and succinate dehydrogenases showed their strongest activity in the respiratory epithelia, while lactate dehydrogenase showed a high level of activity in the tissues that are known to be capable of glycolysis. Following the administration of Frescon, a marked loss in the activity of isocitrate dehydrogenase and NADPH diaphorase occurred.It is postulated that the molluscicide toxin may interfere with cellular respiration, especially in the exposed areas of the body.