Alpha-glycerophosphate Dehydrogenase Activity Research Articles

Evidence of kidney chemical thermosuppression in temperature-acclimated hamsters

1. 1. Adult male golden hamsters ( Mesocricetus auratus) were acclimated at three environmental temperatures ( 35±0·5, 23±0.·5 and 6±1° C ) for 3–6 months. 2. 2. the body weight of the heat-acclimated hamsters was significantly lower than that of the controls, whereas there was no difference between the weight of the controls and cold-acclimated animals ( P</0·01). The kidney weight ratios in each temperature group were significantly different ( P⩽0·001), being highest in the cold and lowest in the heat. 3. 3. The total kidney protein was highest in the cold-acclimated animals and lowest in the heat-acclimated animals ( P⩽0·001). 4. 4. The specific and total kidney alpha-glycerophosphate dehydrogenase activity was elevated during cold acclimation and reduced during heat acclimation. 5. 5. The total kidney activity of isocitric dehydrogenase was significantly higher in the cold than in the control and heat-acclimated animals which were equal. 6. 6. The results support the concept that there are physiological-chemical-metabolic feedback mechanisms that increase the thermogenic response during cold acclimation and suppress it during heat acclimation.

Cytochemical study of dehydrogenases in spermatozoa of older men

Succinic dehydrogenase and alpha-glycerophosphate dehydrogenase activity were demonstrated in spermatozoa of healthy men over 60 yr and in those of in old men, Among the spermatozoa of young men both activities were equally distributed, in old men, however, there was large variation among the spermatozoa within the same ejaculate.

The effect of acute infection with Diplococcus pneumoniae on hepatic mitochondrial alpha-glycerophosphate dehydrogenase activity.

The effect of acute infection with Diplococcus pneumoniae on hepatic mitochondrial alpha-glycerophosphate dehydrogenase activity.

Enzymatic-histochemical studies in experimental uraemia.

Permeability of the cerebral capillaries, transcellular transport of fluids, glucose and ions depend on the condition of the cell membrane. Enzymes which catalyse the energy-releasing processes are important factors in this respect. In uraemia, of ATP-ase, alkaline phosphomonoesterase activity was significantly diminished in the basement membrane of the capillaries and in the cell membranes of the pericapillary glial processes. Decreased activity of these enzymes in uraemia may increase cerebral capillary permeability, the initial phenomenon of uraemic neuropathological alterations. Disturbance in cell membrane transport in uraemia is further revealed by the pericapillary increase in the activity of alpha glycerophosphate dehydrogenase. Hypernatraemia and hyperkalaemia are supposed to promote this phenomenon. The present investigations have shown that the development of uraemia is accompanied in the cerebellum by decreased activity of succinic dehydrogenase and (to a lesser extent) alpha glycerophosphate dehydrogenase, and a considerably increased activity of lactic dehydrogenase. Anaerobic instead of oxidative glycolysis seems to get the upper hand in the energy-releasing metabolic processes of the nerve tissues in uraemia.

Dissociation between thyroxine metabolism and hormonal action in phenobarbital-treated rats.

Phenobarbital injection reduces the biologic effectiveness of thyroxine in thyroidectomized rats maintained on a constant daily dose of hormone. This was inferred from measurements of total body oxygen consumption and the activity of the mitochondrial enzyme alpha-glycerophosphate dehydrogenase in liver, heart and kidney. No changes in these parameters were observed when intact rats were given phenobarbital alone. Thus, the increased hepatocellular binding and deiodination of T4 stimulated by phenobarbital is not related to the biologic action of the hormone. On the contrary, phenobarbital administration reduces the biologic effectiveness of administered thyroxine by diverting hormone from extrahepatic and from specific intrahepatic sites of action. (Endocrinology 88: 115, 1971)

Free fatty acid inhibition of alpha-glycerophosphate dehydrogenase activity in rat brain.

Free fatty acid inhibition of alpha-glycerophosphate dehydrogenase activity in rat brain.

Effect of diet on linoleic acid desaturation and on some enzymes of carbohydrate metabolism

The effect of diet on the desaturation of linoleic acid to gamma-linolenic acid by liver microsomal preparations, on blood glucose and insulin levels, and on activities of glucokinase, hexokinase, pyruvate kinase, and alpha-glycerophosphate dehydrogenase have been studied. The female rats used in these experiments were maintained on one of the following dietary regimes: (a) fasted, (b) fasted for 96 hr and refed glucose, (c) balanced diet, (d) carbohydrate-free diet, (e) lipid-free diet, or (f) protein-free diet. Fasting for 96 hr caused a decrease of both linoleic acid desaturation and glucokinase and pyruvate kinase activity together with a slight decrease of the blood insulin level. Alpha-glycerophosphate dehydrogenase activity was not modified. Refeeding of glucose for 50 hr increased the conversion of linoleic acid to linolenic acid as well as the activities of all the enzymes studied except alpha-glycerophosphate dehydrogenase. The increase in desaturation, however, was transient. The feeding of a lipid-free diet did not modify the tested parameters. Feeding a carbohydrate-free diet for 96 hr resulted in increased linoleic acid desaturation but decreased glucokinase and pyruvate kinase activity, thus apparently eliminating a putative correlation between the fatty acid desaturating activity and glycolytic activity or blood insulin levels under these experimental conditions. The findings suggest that dietary proteins may play an important role in determining the level of fatty acid desaturation.

Citrate-cleavage enzyme, 'malic' enzyme and certain dehydrogenases in embryonic and growing chicks.

The activities of several enzymes possibly implicated in lipogenesis were measured in the soluble fraction of homogenates of liver and adipose tissue of embryonic and growing chicks. The activities of adipose-tissue enzymes showed little or no change. The activities of hepatic hexose monophosphate-shunt dehydrogenases, malate dehydrogenase, 3-phosphoglyceraldehyde dehydrogenase and NAD-linked alpha-glycerophosphate dehydrogenase also showed little or no change. Isocitrate dehydrogenase activity in liver rose to a peak on the day of hatching and fell to half the peak value during the next 12 days, where it remained to 26 days after hatching. The activities of ;malic' enzyme and citrate-cleavage enzyme showed very low stable values in embryonic liver and remarkable rises during the early part of the post-hatching period. An 85-fold increase in the activity of ;malic' enzyme activity was completed in 7 days and a 15-fold increase in that of citrate-cleavage enzyme in 5 days. The activities then attained were maintained up to 26 days after hatching. 2. The increases in the activities of hepatic citrate-cleavage enzyme and ;malic' enzyme occurred simultaneously with a marked increase in lipogenesis, suggesting a relationship of these enzymes to lipogenesis in chick liver. By contrast, activity of the hexose monophosphate-shunt dehydrogenases does not appear to be thus associated.

The distribution of monoamine oxidase and alpha-glycerophosphate dehydrogenase in pig brain.

Activities of the enzymes monoamine oxidase (EC 1.4.3.4), alpha-glycerophosphate dehydrogenase (EC 1.1.99.5) and cytochrome oxidase (EC 1.9.3.1) were determined in homogenates and in the mitochondrial fraction prepared from individual regions of pig brain. The variation in the activity of alpha-glycerophosphate dehydrogenase paralleled that of cytochrome oxidase, but this was not the case with monoamine oxidase. The differences in the activities of the enzymes among homogenates of the various regions of the brain persisted in mitochondria prepared from these homogenates. The purification of these three enzymes paralleled each other when mitochondria were prepared, suggesting that the three enzymes are bound to the same particles.

A Comparative Study of the Activities of Alpha-Glycerophosphate Dehydrogenase and Lactic Dehydrogenase in Muscles of the Mouse, Rat, Frog, and American Cockroach

A Comparative Study of the Activities of Alpha-Glycerophosphate Dehydrogenase and Lactic Dehydrogenase in Muscles of the Mouse, Rat, Frog, and American Cockroach

Alpha-glycerophosphate dehydrogenase and glucose-6-phosphate dehydrogenase in tissues of the Weddell seal.

High activity of alpha-glycerophosphate dehydrogenase and low activity of glucose-6-phosphate dehydrogenase in adipose tissue of Weddell seals suggest that neutral fat may be assembled there from exogenous sources of fatty acids. Low activity of glucose-6-phosphate dehydrogenase in other tissues tested precludes assignment of the function of fatty-acid synthesis to any specific tissue and emphasizes uniqueness of adipose mass in seals.

Age changes in size and number of the giant mitochondria in the flight muscle of the common housefly ( Musca domestica L.)

Changes in the giant mitochondria (sarcosomes) in the flight muscles of the ageing housefly Musca domestica L. have been quantitatively determined and the results incorporated in the present paper. Variations in mitochondrial size and number are both sex-related and age-dependent. In the male fly both mean size as well as the total number of mitochondria per fly increase up to the beginning of the second week and then begin to decline by the end of the second week. In the female, the maximum size and number are also reached by the third day and remain unchanged until the end of the third week, at which time both size and number then show a dramatic decline. From observations of specific changes in the populations of differently sized sarcosomes, it is inferred that multiplication, growth, and lysis of mitochondria are continuous processes throughout the life-span of the flies, but that their rates differ with age. In the male fly these changes in size and number of the mitochondria are preceded by the loss of wings and a decline in ATP-ase and in alpha-glycerophosphate dehydrogenase activities, whereas in the female fly such mitochondrial variations occur with the decline in the physical and biochemical functions of flight.

EFFECT OF ADRENALECTOMY ON RAT LIVER MITOCHONDRIA.

Bilateral adrenalectomy results in an increase in the mitochondrial alpha-glycerophosphate dehydrogenase activity in rat liver, a decrease in liver alphaglycerophosphate, and a lowered alphaglycerophosphate to dihydroxyacetone phosphate ratio. There was no change in the rates of oxidation of succinate and beta-hydroxybutyrate. Malic dehydrogenase, lactic dehydrogenase, NADPH-cytochrome-c reductase and succinic-cytochrome-c reductase activities were similar in adrenalectomized and control animals.

Mitochondrial alpha-glycerophosphate dehydrogenase activity of juxtaglomerular cells in experimental hypertension and adrenal insufficiency.

SummaryNon-coenzyme linked a-glycerophosphate dehydrogenase activity has been demonstrated histochemically in juxtaglomerular cells of rats. Menadione, which increased the activity of rat kidney mitochondria 4- to 5-fold in vitro, was required as intermediate electron carrier when a thiazol substituted monotetrazole was used as final H-acceptor in tissue sections. a-Glycerophosphate dehydrogenase activity of juxtaglomerular cells increased both in ischemic kidneys from renal hypertensive rats and in kidneys from adrenal insufficient animals. Decrease in activity of juxtaglomerular cells was noted both in untouched kidneys from animals bearing a unilateral arterial clamp and in the renal cortex of rats overdosed with DOCA on a high sodium diet.