Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.1.1 (hexokinase)
 5,274 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The maximal rate of some cerebral enzymatic activities related to energy transduction (hexokinase; phosphofructokinase; lactate dehydrogenase; citrate synthase; malate dehydrogenase; total NADH-cytochrome c reductase; cytochrome oxidase), amino acid metabolism (glutamate decarboxylase; glutamate dehydrogenase) and cholinergic metabolism (acetylcholine esterase) were tested in the cerebral cortex and in sub-cortical area of rats. The evaluations were performed both in the homogenate in toto and in the crude mitochondrial fraction, before and after a postdecapitative normothermic ischemia of 5, 10, 20, and 40 min duration. The results are discussed also with respect to the pharmacological pretreatment with two biological substances which may modulate amino acid (L-alanine) and phospholipid metabolism (CDP-choline). The analysis of the present data suggests the occurrence in brain tissue of a variety of interrelated factors implicated in the ischemia-induced changes of the maximal rate of the enzymatic activities related to the energy transduction. These include: (a) rearrangement of the enzymatic activities because of the changed metabolic and chemico-physical condition; (b) decrease in the activity of enzymes related to the electron transfer chain and glycolysis; (c) changes in enzymes related to mitochondrial membranes. The effects of in vivo administration of alanine or CDP-choline, even if significant, are not consistent throughout the time period studied.
 ...
PMID:Changes induced by ischemia on some cerebral enzymatic activities related to energy transduction and amino acid metabolism. 685 30

The aim of the present study is to compare normal and tumoral pancreatic islet cells in terms of both the activity of selected cytosolic and mitochondrial enzymes participating to nutrient catabolism and the intrinsic properties of FAD-glycerophosphate dehydrogenase. The activity of the glycolytic enzymes hexokinase and lactate dehydrogenase was higher in tumoral (RINm5F) than normal islet cells. The opposite was seen for glutamate decarboxylase, glutamate-oxaloacetate transaminase, glutamate-pyruvate transaminase, glutamate dehydrogenase, 2-ketoglutarate dehydrogenase and FAD-glycerophosphate dehydrogenase (m-GDH). These findings are consistent with the high rates of glycolysis and protein synthesis seen in tumoral islet cells compared with normal islet cells, which favour mitochondrial oxidative events associated with the catabolism of D-glucose and amino acids. The intrinsic catalytic properties of m-GDH were comparable, albeit not identical, in normal and tumoral islet cells. Since a deficiency of m-GDH in pancreatic islets may represent a contributing factor in the pathogenesis of non-insulin-dependent diabetes, it is proposed that RINm5F cells may readily yield sufficient islet m-GDH for purification and further gene cloning.
 ...
PMID:Activity of cytosolic and mitochondrial enzymes participating in nutrient catabolism of normal and tumoral islet cells. 776 86

The mechanism of action of the antiepileptic drug lamotrigine has previously been investigated only in acute experiments and is thought to involve inhibition of voltage-dependent sodium channels. However, lamotrigine is effective against more forms of epilepsies than other antiepileptic drugs that also inhibit sodium channels. We investigated whether chronic lamotrigine treatment may affect cerebral amino acid levels. Rats received lamotrigine, 10 mg/kg/day, for 90 days. The hippocampal level of GABA increased 25%, and the activities of glutamate decarboxylase and succinic semialdehyde/GABA transaminase increased 12 and 21% (p< 0.05), respectively, indicating increased GABA turnover. The uptake of GABA and glutamate into proteoliposomes remained unaltered. The level of taurine increased 27% in the hippocampus and 16% in the frontal and parietal cortices. The activities of hexokinase and alpha-ketoglutarate dehydrogenase, remained at control values. Serum lamotrigine was 41.7+/-1.5 microM (mean+/-S.E.M.), which is within the range seen in epileptic patients. Acute experiments with 5, 20 or 100 mg lamotrigine/kg, caused no changes in brain amino acid levels. The results suggest that chronic lamotrigine treatment increases GABAergic activity in the hippocampus. The cerebral increase in taurine, which has neuromodulatory properties, may contribute to the antiepileptic effect of lamotrigine.
 ...
PMID:Chronic lamotrigine treatment increases rat hippocampal GABA shunt activity and elevates cerebral taurine levels. 1116 4