Abstract:
:Lysophospholipids are generated during the turnover and breakdown of membrane phospholipids. We have identified and partially characterized three enzymes involved in the metabolism of lysophospholipids in human brain, namely, lysophospholipase, lysophospholipid:acyl-CoA acyltransferase (acyltransferase), and lysophospholipid:lysophospholipid transacylase (transacylase). Each enzyme displayed comparable levels of activity in biopsied and autopsied human brain, although in all cases the activity was somewhat lower in human than that in rat brain. All three enzymes were localized predominantly in the particulate fraction, with lysophospholipase possessing the greatest activity followed by acyltransferase and transacylase. Lysophosphatidylcholine possessed a Km in the micromolar range for lysophospholipase and transacylase, and in the millimolar range for acyltransferase, whereas arachidonyl-CoA displayed a Km in the micromolar range for acyltransferase. The three enzymes differed in their pH optima, with lysophospholipase being most active at pH 8.0, transacylase at pH 7.5, and acyltransferase at pH 6.0. Both bromophenacyl bromide and N-ethylmaleimide inhibited lysophospholipase activity and, to a lesser extent, that of acyltransferase and transacylase. None of the enzyme activities were affected by the presence of dithiothreitol or EDTA, although particulate lysophospholipase was activated approximately two-fold by the addition of 5 mM MgCl2 or CaCl2 but not KCl. Transacylating activity was stimulated by CoA, the EC50 of activation being 6.8 microM. Acyltransferase displayed an approximately threefold preference for arachidonyl-CoA over palmitoyl-CoA, whereas the acylation rate of different lysophospholipids was in the order lysophosphatidylinositol > 1-palmitoyl lysophosphatidylcholine > 1-oleoyl lysophosphatidylcholine > lysophosphatidylserine > lysophosphatidylethanolamine. This, and the preference of human brain phospholipase A2 for phosphatidylinositol, suggests that this phospholipid may possess a higher turnover rate than the other phospholipid classes examined. Human brain homogenates also possessed the ability to transfer fatty acid from lysophosphatidylcholine to lysophosphatidylethanolamine. In addition, we also present evidence that diacylglycerophospholipids can act as acyl donors for the transacylation of lysophospholipids. We have therefore demonstrated the presence of, and partially characterized, three enzymes that are involved in the metabolism of lysophospholipids in human brain. Our results suggest that lysophospholipase may be the major route by which lysophospholipids are removed from the cell membrane in human brain. However, all three enzymes likely play an important role in the remodeling of membrane composition and thereby contribute to the overall functioning of membrane-associated processes.
journal_name
J Neurochemjournal_title
Journal of neurochemistryauthors
Ross BM,Kish SJdoi
10.1046/j.1471-4159.1994.63051839.xsubject
Has Abstractpub_date
1994-11-01 00:00:00pages
1839-48issue
5eissn
0022-3042issn
1471-4159journal_volume
63pub_type
杂志文章abstract::The microtubule-based motor protein kinesin is thought to drive anterograde organelle transport in axons, but nothing is known about how its force-generating activity or organelle-binding properties are regulated. Studies in other motility systems suggest that protein phosphorylation is a reasonable candidate for this...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1993.tb03513.x
更新日期:1993-06-01 00:00:00
abstract::The nature of postsynaptic sites involved in the uptake and metabolism of striatal 3,4-dihydroxyphenylethylamine (dopamine, DA) was investigated. The accumulation of [3H]DA (10(-7) M) into slices of rat striatum was found to be greatly dependent (greater than 99%) on the presence of sodium ion in the incubation medium...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1985.tb07164.x
更新日期:1985-06-01 00:00:00
abstract::A dipeptidyl aminopeptidase was partially purified from a supernatant fraction of bovine adrenal medulla by gel filtration and anion-exchange chromatography. From gel filtration, the apparent molecular weight of the enzyme was 68,100 and its pH optimum was 9.5. Its Km for hydrolysis of the synthetic substrate arginyla...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1988.tb13226.x
更新日期:1988-01-01 00:00:00
abstract::Microdialysis in the awake, freely moving rat was used to determine the effect of pyrithiamine-induced thiamine deficiency on the levels of amino acids in the brain. Studies were carried out on (a) presymptomatic animals immediately before the development of behavioral changes and (b) acute symptomatic animals within ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1993.tb03635.x
更新日期:1993-09-01 00:00:00
abstract::We have studied the responsiveness of vascular adenylate cyclase to vasoactive intestinal peptide (VIP) and parathyroid hormone (PTH) using preparations of cerebral microvessels and arteries. Cerebral microvessels obtained from rats, guinea-pigs, cattle, and pigs all responded potently to bovine (b) PTH-(1-34), wherea...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1984.tb12808.x
更新日期:1984-09-01 00:00:00
abstract::We examined the effects of chronic ethanol exposure on the levels of N-methyl-D-aspartate receptor subunit 1 (NMDAR1) protein, an essential component of N-methyl-D-aspartate glutamate receptors, in rat brain. By immunoblotting procedures using a specific antibody for the NMDAR1 subunit, we found that ethanol dramatica...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1994.62041635.x
更新日期:1994-04-01 00:00:00
abstract::Sequence variation was found in cDNA coding for the extracellular domain of the rat gamma-aminobutyric acid type A (GABAA) receptor alpha 6 subunit. About 20% of polymerase chain reaction (PCR)-amplified alpha 6 cDNA prepared from rat cerebellar mRNA lacked nucleotides 226-255 as estimated by counting single-stranded ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1994.63031167.x
更新日期:1994-09-01 00:00:00
abstract::Ethanol provides neuroprotection following ischemia/reperfusion. This study assessed ethanol's effect on hyperglycolysis and NADPH oxidase (NOX) activation. Adult, male Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h. Three sets of experiments were conducted to determine ethanol's...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.12169
更新日期:2013-07-01 00:00:00
abstract::Myelin-deficient (mld) is a complex mutation affecting the myelin basic protein (MBP) locus of the mouse. It consists of duplication and partial inversion of the MBP gene and results in a dysfunctional MBP locus. The mutant phenotype is reversed, both in vivo and in vitro, in approximately 5% of mld oligodendrocytes. ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1997.68020457.x
更新日期:1997-02-01 00:00:00
abstract::The normal developmental profile of preprotachykinin (PPT) gene expression was determined in rat striatum from embryonic day 20 to adulthood (greater than 45 days of age). At embryonic day 20, the amount of striatal PPT mRNA was approximately 8% of adult levels, and this specific mRNA approached adult levels by postna...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb04557.x
更新日期:1990-09-01 00:00:00
abstract::Autism is a behaviorally defined neurodevelopmental disorder and among its symptoms are disturbances in face and emotional processing. Emerging evidence demonstrates abnormalities in the GABAergic (gamma-aminobutyric acid) system in autism, which likely contributes to these deficits. GABA(B) receptors play an importan...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2010.06858.x
更新日期:2010-09-01 00:00:00
abstract::Aminoguanidine inhibits the development of retinopathy in diabetic animals, but the mechanism remains unclear. Inasmuch as aminoguanidine is a relatively selective inhibitor of the inducible isoform of nitric oxide synthase (iNOS), we have investigated the effects of hyperglycemia on the retinal nitric oxide (NO) path...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.0022-3042.2001.00737.x
更新日期:2002-03-01 00:00:00
abstract::A vesicular glutamate transporter (VGLUT) is responsible for the accumulation of l-glutamate in synaptic vesicles in glutamatergic neurons. Two isoforms, VGLUT1 and VGLUT2, have been identified, which are complementarily expressed in these neurons. Mammalian pinealocytes, endocrine cells for melatonin, are also glutam...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.2003.01532.x
更新日期:2003-01-01 00:00:00
abstract::A mass fragmentographic method for the determination of trace amounts of amino acid neurotransmitter candidates from brain perfusates is described. The analytical procedure includes the measurements of glycine, beta-alanine, gamma-aminobutyric acid, proline, aspartic acid, and glutamic acid; alpha-alanine, leucine, an...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1982.tb08650.x
更新日期:1982-02-01 00:00:00
abstract::We examined the effect of phenylalanine (50-400 microM) on the electrically stimulated release of endogenous 3,4-dihydroxyphenylethylamine (dopamine or DA) from superfused rat striatal slices. In the absence of tyrosine, phenylalanine (25 microM) partially sustained DA release, but less well than an equimolar concentr...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1986.tb00777.x
更新日期:1986-11-01 00:00:00
abstract::The role of the serotonin (5-hydroxytryptamine) autoreceptor in the regulation of the activity of tryptophan hydroxylase was investigated in rat raphe slices. The activity of tryptophan hydroxylase was estimated by measuring the accumulation of 5-hydroxytryptophan in the presence of inhibition of aromatic L-amino acid...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1986.tb13063.x
更新日期:1986-03-01 00:00:00
abstract::Obesity is a worldwide health problem that urgently needs to be solved. Leptin is an anti-obesity hormone that activates satiety signals to the brain. Evidence to suggest that leptin resistance is involved in the development of obesity is increasing; however, the molecular mechanisms involved remain unclear. We herein...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.13057
更新日期:2015-05-01 00:00:00
abstract::Recovery of AChE activity in the motor end plate region and end plate free region of the rat diaphragm was studied after irreversible inhibition by soman. Recovery was slow during the first 2 days and only 4 S and 10 S molecular forms of AChE were present in the end plate region. However, cytochemical evidence indicat...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1981.tb04478.x
更新日期:1981-10-01 00:00:00
abstract::The Na+-dependent synaptosomal uptakes of proline, aspartic acid, glutamic acid, and gamma-aminobutyric acid were strong inhibited by monounsaturated fatty acids. With oleic acid, half-maximal inhibition was observed at about 15 microM. The Na+-independent uptakes of leucine, phenylalanine, histidine, and valine were ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1982.tb07898.x
更新日期:1982-05-01 00:00:00
abstract::A cDNA clone encoding a novel G protein-linked receptor was isolated from a rat cerebral cortex cDNA library using a polymerase chain reaction-amplified cDNA fragment as a probe. This 2.4-kb clone encodes a 367 amino acid protein with seven putative transmembrane spanning domains. The protein is highly homologous to t...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1995.64010034.x
更新日期:1995-01-01 00:00:00
abstract::At 1, 2, and 4 weeks after unilateral premotor and motor cortex ablation in rats, a significant and lasting decrease in glutamate levels in the ipsilateral versus contralateral striatum was observed. A significant corresponding fall in aspartate was seen only after 1 week. In contrast, there was a large increase in th...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1982.tb05352.x
更新日期:1982-04-01 00:00:00
abstract::The MRC OX-2 monoclonal antibody recognises membrane glycoproteins of Mr 41,000 in rat brain and 47,000 on thymocytes. It also reacts with follicular dendritic cells in lymphoid organs, endothelium, smooth muscle, and B-lymphocytes. Indirect immunoperoxidase staining of cryostat sections showed that OX-2 antigen was p...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1984.tb12844.x
更新日期:1984-10-01 00:00:00
abstract::Disulfide-bridged S100b protein formation, aircatalyzed and induced by thiol/disulfide exchange, was studied under various ionic conditions. As native, physiological disulfide-bridged proteins are obtained easily from their reduced counterparts under appropriate redox conditions, this work was performed to determine w...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb03111.x
更新日期:1990-10-01 00:00:00
abstract::In the present study we have applied a brain microdialysis technique to investigate the effects of ouabain infusion on the release of dopamine, acetylcholine, and amino acids from striatal neurons in freely moving rats. Ouabain caused an increase in the dialysate levels of dopamine; its metabolite 3,4-dihydroxyphenyla...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1989.tb02512.x
更新日期:1989-03-01 00:00:00
abstract::The turnover of acetylcholine (ACh) in rat brain synaptosomes and its compartmentation in the labile bound and stable bound pools were investigated. The P(2) fraction from rat brain was subjected to three sequential incubations, each terminated by centrifugation followed by determination of ACh concentrations by gas c...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1981.tb00423.x
更新日期:1981-05-01 00:00:00
abstract::Current evidence indicates that glutamate acting via the N-methyl-D-aspartate (NMDA) receptor/ion channel complex plays a major role in the neuronal degeneration associated with a variety of neurological disorders. In this report the role of glycine in NMDA neurotoxicity was examined. We demonstrate that NMDA-mediated...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb02329.x
更新日期:1990-03-01 00:00:00
abstract::Traumatic brain injury (TBI) results in significant inflammation which contributes to the evolving pathology. Previously, we have demonstrated that cyclic AMP (cAMP), a molecule involved in inflammation, is down-regulated after TBI. To determine the mechanism by which cAMP is down-regulated after TBI, we determined wh...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.12049
更新日期:2012-12-01 00:00:00
abstract::Glial cells secrete proinflammatory mediators in the brain in response to exogenous stimuli such as infection and injury. Previously, we documented that systemic maternal lipopolysaccharide (LPS)-exposure at embryonic gestation day 18 causes oligodendrocyte (OL)-injury/hypomyelination in the developing brain which can...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2007.05199.x
更新日期:2008-05-01 00:00:00
abstract::The structure and function of mitochondrial respiratory-chain enzyme proteins were studied postmortem in the substantia nigra of nine patients with Parkinson's disease and nine matched controls. Total protein and mitochondrial mass were similar in the two groups. NADH-ubiquinone reductase (Complex I) and NADH cytochro...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb02325.x
更新日期:1990-03-01 00:00:00
abstract::Cocaine- and amphetamine-regulated transcript (CART) is a peptide neurotransmitter that has been implicated in drug reward and reinforcement. CART mRNA and peptide expression are highly concentrated in several compartments of the mesolimbic reward pathway. Several lines of evidence suggest that CART peptides may contr...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2006.03745.x
更新日期:2006-04-01 00:00:00