bluuebunny/crossref_metadata_2025_split huggingface dataset:
OXIDATIVE PHOSPHORYLATION IN MITOCHONDRIA OF DEVELOPING RAT BRAIN
Authors: Milstein J. M. , White J. G. , Swaiman K. F. 
Published: October 2006

Abstract—

Oxygen uptake, ADP/O ratios and respiratory control ratios (RCR) were studied by oxygen electrode techniques in mitochondria prepared from developing rat brain.
Oxygen consumption, ADP/O ratios and RCR based on mitochondrial protein concentration increased with maturation. Of the substrates employed, succinate supported oxygen uptake best and malate poorest.
The addition of exogenous NAD to the mitochondrial preparation had no effect on rate of oxygen uptake.
Lack of change in ADP/O ratio in the presence of glucose, a tricarboxylic acid cycle intermediate (α‐oxoglutarate), and ATP leads us to believe that there is no significant hexokinase activity in this preparation.
SYNTHESIS OF ADENOSINE TRIPHOSPHATE BY MYELIN OF SPINAL NERVES OF RABBIT1
Authors: Miani N. , Cavallotti C. , Caniglia A. 
Published: October 2006

Abstract—

The myelin fraction isolated by isopycnic gradient centrifugation from rabbit nerve is able to synthesize ATP at substrate level through the Embden‐Meyerhof pathway. Suitable conditions are described to preserve the association of glycolytic enzymes with isolated myelin.
Except for phosphofructokinase and ketose‐1‐phosphate aldolase, all the remaining glycolytic enzymes are present in the myelin. A wide divergence was found in the firmness of the association of individual glycolytic enzymes with myelin under the condition of isolation; some, like glucosephosphate isomerase and glyceraldehydephosphate dehydrogenase were retained in high percentage (about 60 per cent of the activity of the homogenate is myelin‐bound); others were weakly bound (no more than 7–6 percent of the lactate dehydrogenase activity of the homogenate is myelin‐bound).
By using glyceraldehyde‐3‐phosphate as substrate for glycolysis, about 25 per cent of the total glycolytic activity of rabbit‐nerve homogenate is associated with the myelin.
Glucosephosphate isomerase and lactate dehydrogenase may be extracted from and readily recombined with the myelin.
SYNTHESIS OF SULPHATIDE‐CONTAINING LIPOPROTEINS IN RAT BRAIN1
Authors: Herschkowitz N. , McKhann G. M. , Saxena S. , Shooter E. M. , Herndon R. 
Published: October 2006

Abstract—

Puromycin inhibits [14C]leucine Hincorporation into brain proteins, but has no effect on the incorporation of [35S]sulphate into sulphatide. These effects of puromycin are observed not only with the proteins and sulphatide of whole brain, but also with the protein and sulphatide portion of water‐soluble lipoprotein complexes.
Microsomes can be separated into three subfractions which differ chemically, morphologically and metabolically. Protein synthesis and sulphatide synthesis are located in different submicrosomal fractions.
The addition of water‐soluble brain proteins to the incubation medium causes release of newly synthesized [35S]sulphatide and formation of soluble sulphatide protein complexes. One acceptor protein is identified as the lipoprotein previously shown to bind [35S]sulphatide in vivo (Herschkowitz, McKhann, Saxena and Shooter, 1968b).
These results suggest that protein and sulphatide synthesis can function independently and that association of newly synthesized lipid to preformed protein is possible.
VERÄNDERUNGEN DER AMINOSÄUREKONZENTRATIONEN IM RATTENHIRN BEI VERRINGERUNG DER K+‐ZUFUHR IN VIVO
Authors: Gründig E. , Hanbauer I. 
Published: October 2006

Zusammenfassung—

Bei Verfütterung des Kationenaustauschers Resonium A an Ratten konnte im ZNS keine Abnahme der K+‐Konzentration gefunden werden wie etwa im Lebergewebe. Hingegen stieg der K+‐Gehalt in ‘Cortex’ und ‘Striatum’ leicht an.
Gleichzeitig erhöhte sich die Konzentration der freien Aminosäuren in ‘Cortex’, ‘Striatum’, ‘Thalamus’ und Cerebellum—für Glutaminsäure nur etwa um 70–80 Prozent, die der meisten übrigen Aminosäuren auf das 2–3 fache: am stärksten war der Anstieg von GABA und Glycin.
K+‐Restitution durch K+‐reiche Kost führte nach 7 Tagen zur Normalisierung des Aminosäuren‐Gehaltes in ‘Cortex’ und Cerebellum; in ‘Striatum’ und ‘Thalamus’ konnte ein Overshoot beobachtet werden.
Das Analysenverfahren zur Bestimmung der Konzentrationen freier Aminosäuren im Hirngewebe wird diskutiert.
METABOLISM OF THE PHOSPHOINOSITIDES IN GUINEA‐PIG BRAIN SYNAPTOSOMES
Authors: Harwood J. L. , Hawthorne J. N. 
Published: October 2006

Abstract— The subcellular distribution of a number of enzymes concerned with inositol lipid metabolism has been studied in sub‐fractions of disrupted guinea‐pig brain synaptosomes. The enzymes were CDP‐diglyceride: inositol phosphatidate transferase, phospha‐tidylinositol kinase, diphosphoinositide kinase, diphosphoinositide phosphomonoesterase and diphosphoinositide diesterase. The distribution of phosphatidylinositol kinase in sub‐fractions from water‐treated synaptosomes was compared with that of other plasma membrane enzymes. After partial solubilization of synaptosomes by Triton X‐100 the activities of phosphatidylinositol kinase and several other enzymes were examined.Distribution of phosphatidylinositol kinase closely resembled that of acetylcholinesterase in sub‐fractions of synaptosomes. Both enzymes appeared to be localised in the outer membrane of the synaptosome. CDP‐diglyceride: inositol phosphatidate transferase was present in all types of synaptosomal membrane. All three enzymes concerned with diphosphoinositide metabolism were found in the cytoplasm of the synaptosome.
EFFECTS OF ANTIEPILEPTIC DRUGS ON BRAIN ENERGY RESERVES DURING CONVULSIONS1
Authors: King Lucy J. , Carl Juanita 
Published: October 2006

Abstract—Cerebral cortical ATP, P‐creatine, glucose, and lactate were measured 6 sec after 1 sec of 150/sec rectangular pulses, at 0,20 v, 40 v, 60 v, 80 v, or 100 v, applied to the heads of intact mice which had been given either no drug, phenobarbitone (25 mg/kg), trimethadione (600 mg/kg), or diphenylhydantoin (40 mg/kg), intraperitoneally. In general, regardless of stimulus strength or drug used, animals which exhibited maximal (tonic‐clonic) convulsions showed similar striking decreases in brain P‐creatine, decreases in ATP and glucose, and increases in lactate. On the other hand, in animals which exhibited less than maximal clinical response, there was little or no change in these metabolites. An exception was the case of diphenylhydantoin. Tonic‐clonic seizures did not occur after diphenylhydantoin administration, even with 100 v stimuli, but substrate changes at this voltage were, nevertheless, similar to those observed in brains of other mice undergoing maximal convulsions.
STUDIES OF AMINES IN THE STRIATUM IN MONKEYS WITH NIGRAL LESIONS
Authors: Goldstein M. , Anagnoste B. , Battista A. F. , Owen W. S. , Nakatani S. 
Published: October 2006

Abstract—The effects of ventromedial tegmental lesions on the biosynthesis and disposition of biogenic amines in the striatum of monkeys were investigated. The concentrations of endogenous dopamine and of the intraventricularly injected [3H]dopamine were distinctly lower in the striatum on the lesion side than on the intact side.The storage of [3H]dopamine in the caudate nucleus was impaired to a much greater extent than the storage of the newly synthesized [3H]norepinephrine.The concentrations of endogenous serotonin and of the intraventricularly injected [14C]serotonin were lower in the striatum on the lesion side than on the intact side. However following MAO inhibition, the concentration of [14C]serotonin did not differ significantly on the two sides of the caudate nucleus.The in vivo biosynthesis of dopamine from tyrosine was significantly reduced in the striatum on the lesion side. Tyrosine hydroxylase and DOPA decarboxylase activities were decreased on the lesion side of the striatum as compared with the intact side. Thus, the ventromedial tegmental lesions affect the storage and the synthesis of dopamine and serotonin in the ipsilateral striatum.
URIDINE PHOSPHORYLASE FROM RAT BRAIN: CHARACTERISTICS AND DEVELOPMENTAL COURSE
Authors: Guroff G. , Rhoads Carol A. 
Published: October 2006

Abstract—Uridine phosphorylase (uridine: orthophosphate ribosyltransferase; EC 2.4.2.3) from rat brain was purified and its properties were studied. The enzyme resembled preparations made from other mammalian sources. Its pH optimum was between 7·6 and 8·0. An examination of its action on various substrates showed rates of reaction in the order: uridine > deoxyuridine > thymidine > cytidine. The enzyme showed a requirement for phosphate which could also be satisfied by arsenate. The activity of the enzyme was protected from heat inactivation by uridine and by phosphate. In brain and liver the activity of the enzyme increased five‐ to ten‐fold between 10 and 20 days of life. Injections of cortisol or of uridine did not increase the enzymic activity.
A METHOD FOR THE STUDY OF CHOLESTEROL BIOSYNTHESIS IN THE CENTRAL NERVOUS SYSTEM
Authors: Chevallier F. , Gautheron C. 
Published: October 2006

Abstract—

After intraperitoneal injection, there is negligible incorporation of [2‐14C]‐mevalonic lactone into the CNS of the adult rat.
Mevalonic lactone injected into the CSF is quickly transferred to blood.
Mevalonic lactone injected in the cistema magna or the lateral ventricle of the brain does not diffuse readily into the whole CSF. Spinal cord cholesterol is most heavily labelled after intracisternal injection, as is brain cholesterol after intraventricular administration.
After intraventricular perfusion, the diffusion of mevalonic lactone into the ventricle opposite the side of the injection is increased when the rate of perfusion is doubled from 5 to 10 μ1/hr. After injection, optimal homogeneity is obtained if a large volume (70μl) is administered.
An increase in the volume of injection from 70 μl to 130μl does not alter the distribution of activity between the left and right ventricles, nor does it increase the diffusion of mevalonic lactone from ventricle to spinal cord CSF.
The mean yield of mevalonic lactone incorporation into brain cholesterol is much higher after injection than after perfusion of precursor into the lateral cerebral ventricle.
ISOLATION AND IDENTIFICATION OF α‐ASPARTYL‐SERINE, ALANYLPHENYLALANINE AND ISOLEUCYLLEUCINE FROM CALF BRAIN STEM
Authors: Versteeg D. H. G , Witter A 
Published: October 2006

Abstract— A reproducible extraction and fractionation scheme for the isolation of peptides from nervous tissue is described. The low molecular weight fraction, obtained by this procedure from calf brain stem tissue, was further investigated. The presence of N‐acetyl‐aspartic acid, N‐acetyl‐α‐aspartylglutamic acid and pyrrolidone‐2‐carboxylic acid was confirmed. The occurrence of minor quantities of glutamylpeptides, identical with or related to known γ‐glutamyldipeptides and glutathione, was indicated.Three hitherto unknown dipeptides α‐aspartylserine, alanylphenylalanine and isoleucylleucine were identified. Mass spectrometry was used in the final structure analysis.
BRAIN LIPID MODIFICATIONS INDUCED BY ESSENTIAL FATTY ACID DEFICIENCY IN GROWING MALE AND FEMALE RATS
Authors: Galli C. , White H. B. , Paoletti R. 
Published: October 2006

Abstract—Essential fatty acid (EFA) deficiency initiated in rats prior to birth and continued for one year affects brain lipids to an extent which differs in the two sexes. It was found that:(1) Brain weight and lipid content were decreased in deficient conditions, especially in males.(2) Total phospholipids were present in lower concentrations, particularly in the deficient male brain, while the percentage of the major phospholipid classes‐ethanolamine phosphoglyceride (EPG), choline phosphoglyceride (CPG) and serine phosphoglyceride (SPG) did not change.(3) Brain EPG, CPG and SPG had distinctive fatty acid patterns differing greatly in polyunsaturation content. PE acids of control females had elevated monoenes and reduced saturates in comparison with control males. This sex difference was lost in the deficient animals.(4) Polyunsaturated fatty acids of EPG, CPG and SPG were markedly changed in animals lacking dietary linoleic acid. Trienoic (C20 and C22) and docosapentaenoic acids were greatly increased, whereas arachidonic, docosatetraenoic and docosahexaenoic acids were much decreased.(5) In spite of the changes in fatty acid composition each of the three phospholipid classes maintained its particular level of unsaturation during EFA deficiency.(6) EPG aldehydes did not change appreciably in deficient conditions.
SPHINGOLIPIDS OF DEVELOPING HUMAN CENTRAL NERVOUS TISSUE: CHANGES IN COMPOSITION OF SPHINGOSINE BASES12
Authors: Isaacson Elizabeth , Moscatelli Ezio. A. 
Published: October 2006

Abstract—Developmental changes in composition of sphingosine bases of cerebrosides, sulphatides and sphingomyelins were investigated in samples from brain stem or corpus callosum from premature infants and patients aged 14 months, 39 and 59 years who died of non‐neurological causes. Since insufficient material was obtainable from the premature brains, sulphatides were studied only in older cases. Individual sphingolipids were isolated by combinations of column chromatography and TLC, and were examined for purity by analytical TLC. Sphingosine bases were released by acid‐catalysed methanolysis, and analysed as aldehydes by GLC. Effectiveness and limitations of methods used for analyses of sphingosine bases were evaluated.In contrast to adult sphingolipids in which approximately 95 per cent of the sphingosine bases was 18: sphingosine, as much as 10 per cent of the total was 18: dihydrosphingosine in immature sphingolipids. A compound tentatively identified as 20: sphingosine was present in foetal, infant and adult sphingomyelin at 5, 3 and 1 per cent of the total, respectively. Composition of sphingosine bases of non‐ganglioside sphingolipids in human brain varies with age, presumably in a complex manner.
THE EFFECT OF N‐METHYL‐4‐PIPERIDYL‐DIPHENYL GLYCOLATE ON THE INCORPORATION OF 32P INTO PHOSPHOLIPIDS FROM RAT BRAIN CORTEX SLICES AND ITS SUBCELLULAR LOCALIZATION
Authors: Heilbronn E. , Widlund L. 
Published: October 2006

Abstract—N‐Methy‐4‐piperidy1‐diphenyl glycolate (N‐methy1‐4‐piperidy1 benzilate), an anticholinergic drug, was shown to stimulate 32P‐incorporation into total phospholipids of rat brain cortex slices. Analysis of the total phospholipids showed stimulation in phosphatidic acid, phosphatidylinositol and phosphatidylethanolamine. Stimulated 32P‐incorpora‐tion was accompanied by a decrease in the Qo2 (μ1 O2/mg dry tissue) value. The effects of the drug were compared with those of some other CNS‐active drugs known to interfere with the ACh content of brain; tremorine, oxotremorine and atropine; and in the presence of eserine, with that of the neurotransmitter acetylcholine.Increase of the outer K+‐concentration resulted in increased Qo2 and 32P‐incorporation into the slices. The effect of the glycolate and perhaps that of atropine tended to increase in this medium. Subcellular fractionation of slices showed that the glycolate stimulated 32P‐incorporation occurred mainly in the nerve end fraction. The total amount of the individual phospholipids was not changed, but the specific activity had significantly increased in phosphatidic acid and phosphatidylinositol. The possibility that glycolate‐induced stimulated 32P‐incorporation into nerve end phospholipids is due to increased glycolysis is discussed.
GLUTAMATE METABOLISM IN OCTOPUS BRAIN IN VIVO;ABSENCE OF A WAELSCH EFFECT
Authors: Rose S. P. R. , Cory H. Therese 
Published: October 2006

Abstract— The metabolism of [U‐14C]glutamate was followed in vivo in the octopus Eledone cirrhosa following intracranial injection, and compared with that in the mammalian brain.By contrast with the rat brain, the specific activity of glutamine recovered from Eledone optic and vertical lobes was lower than that of glutamate at short time intervals after injection. Thus the Waelsch effect was not apparent in this species. Again, in contrast with the rat brain, radioactivity could be found in alanine but not in GABA following [U‐14C]glutamate injection. This was compatible with observations made previously in vitro.The significance of these intraspecies differences in metabolism and compartmentation is discussed.
THE INTERACTION BETWEEN PERIPHERAL NERVE POLYANIONS AND ALCIAN BLUE
Authors: Langley O. K. 
Published: October 2006

Abstract—A study of the staining characteristics of Alcian blue in mammalian peripheral myelinated nerve in the presence of added electrolyte has enabled a comparison to be made of polyanions, formerly shown to be present at nodes of Ranvier, with other chemically defined macromolecules present in the same tissue. Two types of polyanion were shown to exist at nodes, one probably carboxylated and the other containing in addition sulphate ester groups. The possible physiological functions of such materials are discussed in relation to the role played by the nodes of Ranvier in conduction of the nerve impulse.
INCORPORATION IN VIVO OF RADIOACTIVE LEUCINE INTO NEURONAL AND GOAL NUCLEAR PROTEINS OF RAT BRAIN
Authors: Burdman J. A. 
Published: October 2006

AbstractPurified neuronal and glial nuclei were separated from rat brain cells. The fraction rich in neuronal nuclei contained 68 ± 9 per cent neuronal nuclei and the fraction rich in glial nuclei contained 89 ± 6 per cent glial nuclei. The fraction rich in neuronal nuclei isolated from cells of adult rat brain incorporated l‐[4,5‐3H]leucine into TCA‐insoluble material at a rate comparable to those of the microsomal and the soluble fractions of the brain, and at a much higher rate than the fraction rich in glial nuclei. The proteins soluble in buffered‐saline, the acid‐soluble deoxyribonucleoproteins, and the residual proteins of the neuronal nuclei are apparently the proteins which account for the higher specific activity of neuronal proteins compared with glial nuclear proteins. In liver and kidney, the incorporation of [3H]leucine into nuclear proteins was lower than into other subcellular fractions from the same organs.
THE ACTIVATION OF THIAMINE DIPHOSPHATASE BY ATP IN RAT BRAIN
Authors: Inoue A. , Shim S. , Iwata H. 
Published: October 2006

Abstract—

Thiamine diphosphatase (TDPase) of brain was activated by a low concentration of ATP.
In thiamine‐deficient rats TDPase activity in the brain increased significantly relative to that in pair‐fed animals, while in liver it decreased by the same amount as in the pair‐fed controls.
Liver TDPase was localized almost entirely in the soluble fraction, but in the brain it was bound to insoluble protein. On treatment with Triton X‐100 brain TDPase activity increased.
The ATP content of the brain of deficient rats, but not the ADP or AMP content, was significantly higher than in the control group. The level of inorganic phosphate in the brain and spinal cord of deficient animals was elevated markedly, while that of P‐creatine was unchanged.
The possible roles of brain TDPase in relation to nerve conduction and the blood‐brain barrier are discussed.
UPTAKE AND RELEASE OF 45Ca BY BRAIN MICROSOMES, SYNAPTOSOMES AND SYNAPTIC VESICLES1,2
Authors: Diamond I. , Goldberg A. L. 
Published: October 2006

Abstract— Microsomes and synaptosomes from rat brain accumulated 4,5Ca against a concentration gradient by an ATP‐dependent process. Calcium accumulation occurred to the same extent in microsomes prepared from white matter and from grey matter, an observation suggesting that calcium uptake may be in part an activity of the axonal membrane. Microsomes and synaptosomes accumulated calcium to a similar extent but less actively than mitochondria. By contrast, synaptic vesicles showed relatively little calcium accumulation. Isotonic concentrations of sucrose, NaCl, KCl and choline chloride inhibited calcium accumulation, with NaCl and KCl the least effective of these inhibitory agents. No consistent effects on calcium uptake were obtained with adenosine 3′,5′‐monophosphate, dibutyryl cyclic AMP or the methyl xanthines.Incubation of prelabelled microsomes resulted in a release of 45Ca, and ATP inhibited this release process. In the absence of added ATP, isotonic NaCl promoted calcium release to a significantly greater extent than KCl choline chloride or sucrose. In the presence of ATP, these agents all promoted a similar degree of release. Adenosine 3′,5′‐monophosphate or agents that affect its metabolism did not significantly affect calcium release. Magnesium ions reduced calcium release under all conditions tested.
THE EFFECTS OF ALTERED ENDOCRINE STATES AND OF ETHER ANAESTHESIA ON MOUSE BRAIN1
Authors: Passonneau Janet V. , Brunner E. A. , Molstad C. , Passonneau Rebecca 
Published: October 2006

Abstract—The effects of ether anaesthesia on metabolites of mouse brain in altered endocrine states has been examined. Alloxan diabetic mice, with elevated levels of blood and brain glucose, exhibited changes in brain metabolites after ether anaesthesia that were comparable to those seen in normal animals. Sympathectomized and/or adrenalectomized mice had decreased levels of brain glucose. The percentage elevation of glucose in the brains of these animals under ether anaesthesia approximated to normal values, although the absolute cerebral levels were lower. Increases in glycogen in the brains of these animals were somewhat diminished. In none of the altered endocrine states were the changes in brain metabolites following ether anaesthesia eliminated.The activity of UDPglucose‐glycogen glucosyltransferase (UDPglucose: glycogen α‐4‐glucosyltransferasee, EC 2.4.1.11) in the mouse brain was measured in the absence and in the presence of glucose‐6‐P. Neither the total activity nor the percentage of the I form (measured in the absence of glucose‐6‐P) was altered by anaesthesia or by the endocrine state of the animal. The Michaelis constants with UDPglucose as substrate for the total and I forms were 0·36 mM and 1·0 mM, respectively. Considerable UDPglucose‐glycogen glucosyltransferase activity was observed in the absence of added glycogen primer. The observed increase in activity in the presence of added glucose‐6‐P was greater than would have been anticipated if the hexose phosphate were acting at only one site.
STUDIES ON THE PROPERTIES OF RETINAL ALCOHOL DEHYDROGENASE FROM THE RAT
Authors: Watkins W. D. , Tephly T. R. 
Published: October 2006

Abstract—An NAD‐dependent alcohol dehydrogenase (alcohol:NAD oxidoreductase; EC 1.1.1.1) has been isolated and partially purified from the retinal cytosol of the rat. Its substrate specificity and sensitivity to inhibitors of hepatic alcohol dehydrogenase have been investigated. Ethanol, 1‐propanol and 1‐butanol served as substrates for this enzyme but the Km values were more than 100‐fold higher than those reported for hepatic alcohol dehydrogenase. Methanol and retinol were unreactive with this alcohol dehydrogenase. Inhibition by pyrazole was observed but the Kt was about 100‐fold higher than the value observed for hepatic alcohol dehydrogenase. n‐Butyraldoxime inhibited retinal alcohol dehydrogenase with a Kt of 2 μM, a value which approximates its Kt for hepatic alcohol dehydrogenase. 1, 10‐Phenanthroline was ineffective as an inhibitor. Oxidation of retinol was observed in retinal homogenates in the presence of NADP but no inhibition was observed with ethanol, methanol or pyrazole. We conclude that oxidation of retinol is not catalysed by soluble retinal alcohol dehydrogenase.