Abstract:
:Tyrosine hydroxylase, the rate-limiting enzyme in catecholamine biosynthesis, catalyzes the conversion of tyrosine to DOPA, Cyclic AMP-dependent protein phosphorylation conditions alter tyrosine hydroxylase activity in rat striatal homogenates. In agreement with other laboratories, we find that short-term pre-incubation (3 min) of extracts under phosphorylating conditions (Mg . ATP, cAMP) increases enzyme activity two- to tenfold over control as measured during a subsequent 15-min assay. We now report that preincubation under phosphorylating conditions for longer periods (30 min) results in a loss of activity to levels equal to or below that of the control enzyme. Addition of purified bovine brain protein kinase catalytic subunit and Mg . ATP enhances activation and increases the rate of inactivation. To demonstrate that inactivation is not associated with proteolytic degradation or irreversible denaturation, the inactivated form of the enzyme can be reactivated. The protein kinase inhibitor protein decreases the activation process and prevents inactivation of the enzyme to below control values. The sedimentation coefficient is not changed by phosphorylation conditions (S = 8.8 +/- 0.1). Although the apparent Km of the enzyme for the 6-methyltetrahydropterine (6-MPH4) cofactor is reduced (0.86 mM, control; 0.32 mM, activated), it is also reduced in the inactivated form (0.38 mM). The Ki for dopamine is increased from 4.5 microM for the control to 28 microM for the activated enzyme, whereas the inactivated form of the enzyme exhibits a Ki of 10 microM. Removal of catecholamines by gel filtration fails to alter activity and the apparent cofactor Km. Moreover, both the activated and the inactivated states persist following gel filtration. It therefore appears that the activation-inactivation process is not mediated solely by the modulation of enzyme feedback inhibition or changes in the Km for 6-MPH4. We also describe a coupled decarboxylase assay in which labeled dopamine is resolved from the precursors tyrosine and DOPA by low-voltage paper electrophoresis.
journal_name
J Neurochemjournal_title
Journal of neurochemistryauthors
Vrana KE,Allhiser CL,Roskoski R Jrdoi
10.1111/j.1471-4159.1981.tb02382.xsubject
Has Abstractpub_date
1981-01-01 00:00:00pages
92-100issue
1eissn
0022-3042issn
1471-4159journal_volume
36pub_type
杂志文章abstract::We have previously purified and characterized a nervous system-specific glycoprotein antigen from adult Drosophila heads, designated Nervana [nerve antigen (NRV)] and identified two separate genes coding for three different proteins. All three proteins share homology with the beta subunits of Na+,K+-ATPase from variou...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1998.71010142.x
更新日期:1998-07-01 00:00:00
abstract::Acetylcholinesterase (AChE) is found both in motor end-plate (MEP)-free and MEP-rich regions of rat or mouse muscle. We studied the developmental aspects of the localization of asymmetric 16S AChE in both regions of the sternocleidomastoid muscle, which has a well-defined zone of motor innervation. In the rat, the pro...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1984.tb02725.x
更新日期:1984-03-01 00:00:00
abstract::The inhibitory effect of an adenosine analogue, R-N6-phenylisopropyl adenosine (R-PIA), of the cholinergic agonist carbachol, and of morphine on 3H efflux from [3H]choline-labeled field-stimulated rat hippocampal slices was compared with that produced by two inhibitors of N- and L-type Ca2+ channels, omega-conotoxin (...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb01973.x
更新日期:1990-04-01 00:00:00
abstract::Hippocampal brain slices were incubated with depolarizing agents or excitatory amino acids either alone or in the presence of excitatory amino acid antagonists [omega-phosphonic alpha-aminocarboxylic acids--2-amino-4-phosphonobutyric acid (AP4), 2-amino-5-phosphonovaleric acid (AP5), or 2-amino-7-phosphonoheptanoic ac...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1987.tb05756.x
更新日期:1987-06-01 00:00:00
abstract::We have correlated myelin membrane structure with biochemical composition in the CNS and PNS of a phylogenetic series of animals, including elasmobranchs, teleosts, amphibians, and mammals. X-ray diffraction patterns were recorded from freshly dissected, unfixed tissue and used to determine the thicknesses of the liqu...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1989.tb08558.x
更新日期:1989-11-01 00:00:00
abstract::Poly A(+) messenger RNA (mRNA) was isolated from the brains of 3-week-old mice and translated in a cell-free system derived from wheat germ. Maximal stimulation of the system by brain mRNA was observed at a relatively low K+ concentration (45 mM) and low mRNA concentration (1-10 microgram/ml). The translational system...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1980.tb07084.x
更新日期:1980-10-01 00:00:00
abstract::The RGS proteins are a recently discovered family of G protein regulators that have been shown to act as GTPase-activating proteins (GAPs) on the G(alpha i) and G(alpha q) subfamilies of the heterotrimeric G proteins. Here, we demonstrate that RGS7 is a potent GAP in vitro on G(alpha i1), and G(alpha o) heterotrimeric...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1998.70051964.x
更新日期:1998-05-01 00:00:00
abstract::The behavior of a microdialysis probe in vivo is mathematically described. A diffusion-reaction model is developed that not only accounts for transport of substances through tissues and probe membranes but also accounts for transport across the microvasculature and metabolism. Time-dependent equations are presented bo...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1991.tb02105.x
更新日期:1991-07-01 00:00:00
abstract::Math2 (NEX-1/NeuroD6) is a member of the basic helix-loop-helix transcription factor family and is involved in neuronal differentiation and maturation. In this study, we identified the genes targeted by Math2 using DNA microarrays and cultured rat cortical cells transfected with Math2. Of the genes regulated by Math2,...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2008.05579.x
更新日期:2008-09-01 00:00:00
abstract::According to the amyloid hypothesis, accumulation of amyloid beta-peptide (A beta) in the brain is the primary pathogenic event in Alzheimer's disease (AD). Recent evidence indicates that A beta within the intravascular space is linked to A beta deposited in the brain suggesting that transport of A beta between the br...
journal_title:Journal of neurochemistry
pub_type: 杂志文章,评审
doi:10.1111/j.1471-4159.2004.02385.x
更新日期:2004-05-01 00:00:00
abstract::The metabolism of L-tryptophan to the neuroactive kynurenine pathway metabolites, L-kynurenine, kynurenate and quinolinate, and the effects of two inhibitors of quinolinate synthesis (6-chlorotryptophan and 4-chloro-3-hydroxyanthranilate) were investigated by mass spectrometric assays in cultured cells and in vivo. Ce...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1995.65052217.x
更新日期:1995-11-01 00:00:00
abstract::The genetic defect in Friedreich's ataxia (FRDA) is the expansion of a GAA·TCC triplet in the first intron of the FXN gene, which encodes the mitochondrial protein frataxin. Previous studies have established that the repeats reduce transcription of this essential gene, with a concomitant decrease in frataxin protein i...
journal_title:Journal of neurochemistry
pub_type: 杂志文章,评审
doi:10.1111/jnc.12302
更新日期:2013-08-01 00:00:00
abstract::The neurotoxin 1-methyl-4-phenylpyridinium ion (MPP+) in the brain striatum has recently been shown to bind at a putatively vesicular site labeled by [3H]tyramine ([3H]TY). Whereas in the rat and mouse striatum MPP+ antagonized TY binding competitively, in the cerebellum there was a mixed-type antagonism, which sugges...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1993.tb03212.x
更新日期:1993-02-01 00:00:00
abstract::The lack of effective therapies for neurodegenerative disorders is one of the most relevant challenges of this century, considering that, as the global population ages, the incidence of these type of diseases is quickly on the rise. Among these disorders, synucleinopathies, which are characterized by the abnormal accu...
journal_title:Journal of neurochemistry
pub_type: 杂志文章,评审
doi:10.1111/jnc.13529
更新日期:2016-10-01 00:00:00
abstract::Elemental (Na, Cl, K) and water contents of leech (Macrobdella decora) neurons and glial cells were determined under steady-state exposure to 4, 10, and 20 mM KCl concentrations (bathing media) using x-ray microanalysis for quantitative digital imaging of frozen hydrated and dried cryosections. Effects of furosemide, ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1988.tb01161.x
更新日期:1988-12-01 00:00:00
abstract::The normal cellular form of prion protein (PrP(C)) has been shown to exhibit a diverse range of biological activities. Several recent studies highlighted potential involvement of PrP(C) in embryogenesis or in regulating stem cell self-renewal and proliferation. In the current study, we employed human embryonic stem ce...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2010.06601.x
更新日期:2010-07-01 00:00:00
abstract::The aim of this study was to investigate the effect of long-term treatment with interferon (IFN)-alpha on the noradrenaline transporter of bovine adrenal medullary cells. Treatment of cultured adrenal medullary cells with IFN-alpha caused a decrease in uptake of [3H]noradrenaline by the cells in time (4-48 h)- and con...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1998.70041441.x
更新日期:1998-04-01 00:00:00
abstract::Parkinson disease (PD) is a prevalent neurodegenerative disease, in which the formation of misfolded and aggregated α-synuclein is a key neuropathological hallmark. Recent studies reveal that extracellular vesicles such as exosomes present a potential mechanism for propagation of pathological α-synuclein throughout th...
journal_title:Journal of neurochemistry
pub_type: 杂志文章,评审
doi:10.1111/jnc.15288
更新日期:2020-12-29 00:00:00
abstract::The γ-secretase complex is composed of at least four components: presenilin 1 or presenilin-2, nicastrin (NCT), anterior pharynx-defective 1 (Aph-1), and presenilin enhancer 2. In this study, using knockout cell lines, our data demonstrated that knockout of NCT, as well as knockout of presenilin enhancer 2, completely...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.13518
更新日期:2016-03-01 00:00:00
abstract::Microglial activation can lead to microglial apoptosis, which may serve to remove highly reactive and possibly neurotoxic microglia. However the loss of microglia may have consequences for future recovery, protection and repair. P53, a nuclear phosphoprotein transcription factor, is critical for activating the express...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2009.06485.x
更新日期:2010-01-01 00:00:00
abstract::Diminished energy metabolism and reduced activity of brain alpha-ketoglutarate dehydrogenase complex (KGDHC) occur in a number of neurodegenerative diseases. The relation between diminished KGDHC activity and altered energy metabolism is unknown. The present study tested whether a reduction in the KGDHC activity would...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2009.05955.x
更新日期:2009-05-01 00:00:00
abstract::We studied the time course of oxidatively modified proteins in the nigrostriatal dopaminergic system following transection of the medial forebrain bundle by quantifying the number of carbonyl groups coupled to striatal and nigral protein homogenates, an index of metal-catalyzed oxidations. We found a striking effect o...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1997.68062458.x
更新日期:1997-06-01 00:00:00
abstract::In vitro, the transport into and release of [3H]deoxycytidine from the isolated choroid plexus, the anatomical locus of the blood-cerebrospinal fluid barrier, were studied separately. By use of the ability of nitrobenzylthioinosine (NBTI) to inhibit deoxycytidine efflux from choroid plexus, the transport of 1 microM [...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1983.tb13593.x
更新日期:1983-05-01 00:00:00
abstract::Several epidemiological and preclinical studies suggest that non-steroidal anti-inflammatory drugs (NSAIDs), which inhibit cyclooxygenase (COX), reduce the risk of Alzheimer's disease (AD) and can lower β-amyloid (Aβ) production and inhibit neuroinflammation. However, follow-up clinical trials, mostly using selective ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.12059
更新日期:2013-01-01 00:00:00
abstract::To better understand metabotropic/ionotropic integration in neurons we have examined the regulation of M1 muscarinic acetylcholine (mACh) receptor signalling in mature (> 14 days in vitro), synaptically-active hippocampal neurons in culture. Using a protocol where neurons are exposed to an EC(50) concentration of the ...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2007.04931.x
更新日期:2007-12-01 00:00:00
abstract::To identify the transductional mechanisms responsible for the neuroprotective effect of nitric oxide (NO) during ischemic preconditioning (IPC), we investigated the effects of this gaseous mediator on mitochondrial Mn-superoxide dismutase (Mn-SOD) expression and activity. In addition, the possible involvement of Ras/e...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2007.04845.x
更新日期:2007-11-01 00:00:00
abstract::Benzodiazepine receptor binding was measured in cerebellar cortex of 15 patients with dominantly inherited olivopontocerebellar atrophy (OPCA). The majority of these patients had a moderate to marked Purkinje cell loss, as judged by the lowered levels of dentate nucleus gamma-aminobutyric acid (GABA), a marker of Purk...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1984.tb02700.x
更新日期:1984-02-01 00:00:00
abstract::Addition of vasoactive intestinal peptide (VIP) to brain homogenates increased the activity of choline acetyltransferase (ChAT) but not that of acetylcholinesterase or glucose-6-phosphate dehydrogenase. Activity of ChAT was increased in the anterior hypothalamus and in the dorsal and ventral hippocampus, but not in th...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1984.tb12721.x
更新日期:1984-04-01 00:00:00
abstract::The effects of muscarinic agonists and depolarizing agents on inositol phospholipid hydrolysis in the rabbit vagus nerve were assessed by the measurement of [3H]inositol monophosphate production in nerves that had been preincubated with [3H]inositol. After 1 h of drug action, carbachol, oxotremorine, and arecoline inc...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1992.tb09392.x
更新日期:1992-08-01 00:00:00
abstract::Head injury was induced in rats by a weight drop device, falling over the left hemisphere. The rats were killed at 15 min, 4 h, and 24 h after injury. Cortical slices were taken from the injured zone, from the corresponding region of the contralateral hemisphere, and from the frontal lobe of both hemispheres. These co...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1989.tb08550.x
更新日期:1989-11-01 00:00:00