Use of Calcium Antagonism for the Characterization of Drug-Evoked Dopamine Release from the Brain of Conscious Rats Determined by Microdialysis

This study concern to characterize the brain tissues to ischemic stroke, gray matter, white matter and CSF using texture analysisto extract classification features from CT images. The First Order Statistic techniques included sevenfeatures. To find the gray level variation in CT images it complements the FOS features extracted from CT images withgray level in pixels and estimate the variation of thesubpatterns. analyzing the image with Interactive Data Language IDL software to measure the grey level of images. The results show that the Gray Level variation and features give classification accuracy of ischemic stroke 97.6%, gray matter95.2%, white matter 97.3% and the CSF classification accuracy 98.0%. The overall classification accuracy of brain tissues 97.0%.These relationships are stored in a Texture Dictionary that can be later used to automatically annotate new CT images with the appropriate brain tissues names.

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Characterization of a neurologic disease induced by a polytropic murine retrovirus: evidence for differential targeting of ecotropic and polytropic viruses in the brain.

Journal of Virology ◽

10.1128/jvi.69.12.8070-8075.1995 ◽

1995 ◽

Vol 69 (12) ◽

pp. 8070-8075 ◽

Cited By ~ 31

Author(s):

J L Portis ◽

S Czub ◽

S Robertson ◽

F McAtee ◽

B Chesebro

Keyword(s):

Neurologic Disease ◽

The Brain

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Implantable neural interfaces

10.1093/oso/9780199674923.003.0050 ◽

2018 ◽

Author(s):

Stefano Vassanelli

Keyword(s):

Brain Function ◽

Large Scale ◽

Ionic Channels ◽

Patch Clamp Technique ◽

Advantages And Disadvantages ◽

Optogenetic Stimulation ◽

Physical Interfaces ◽

The Brain

Establishing direct communication with the brain through physical interfaces is a fundamental strategy to investigate brain function. Starting with the patch-clamp technique in the seventies, neuroscience has moved from detailed characterization of ionic channels to the analysis of single neurons and, more recently, microcircuits in brain neuronal networks. Development of new biohybrid probes with electrodes for recording and stimulating neurons in the living animal is a natural consequence of this trend. The recent introduction of optogenetic stimulation and advanced high-resolution large-scale electrical recording approaches demonstrates this need. Brain implants for real-time neurophysiology are also opening new avenues for neuroprosthetics to restore brain function after injury or in neurological disorders. This chapter provides an overview on existing and emergent neurophysiology technologies with particular focus on those intended to interface neuronal microcircuits in vivo. Chemical, electrical, and optogenetic-based interfaces are presented, with an analysis of advantages and disadvantages of the different technical approaches.

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Hydrolysis of the brain dipeptide N-acetyl-L-aspartyl-L-glutamate. Identification and characterization of a novel N-acetylated alpha-linked acidic dipeptidase activity from rat brain.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)47823-4 ◽

1987 ◽

Vol 262 (30) ◽

pp. 14498-14506

Author(s):

M B Robinson ◽

R D Blakely ◽

R Couto ◽

J T Coyle

Keyword(s):

Rat Brain ◽

Hydrolysis Of ◽

The Brain ◽

Identification And Characterization ◽

Dipeptidase Activity

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A Role for Xanthurenic Acid in the Control of Brain Dopaminergic Activity

International Journal of Molecular Sciences ◽

10.3390/ijms22136974 ◽

2021 ◽

Vol 22 (13) ◽

pp. 6974

Author(s):

Omar Taleb ◽

Mohammed Maammar ◽

Christian Klein ◽

Michel Maitre ◽

Ayikoe Guy Mensah-Nyagan

Keyword(s):

Dopamine Release ◽

Intraperitoneal Administration ◽

Glutamate Transporter ◽

Fold Increase ◽

Xanthurenic Acid ◽

Metabotropic Receptors ◽

Parent Molecule ◽

Dopaminergic Activity ◽

The Brain

Xanthurenic acid (XA) is a metabolite of the kynurenine pathway (KP) synthetized in the brain from dietary or microbial tryptophan that crosses the blood-brain barrier through carrier-mediated transport. XA and kynurenic acid (KYNA) are two structurally related compounds of KP occurring at micromolar concentrations in the CNS and suspected to modulate some pathophysiological mechanisms of neuropsychiatric and/or neurodegenerative diseases. Particularly, various data including XA cerebral distribution (from 1 µM in olfactory bulbs and cerebellum to 0.1–0.4 µM in A9 and A10), its release, and interactions with G protein-dependent XA-receptor, glutamate transporter and metabotropic receptors, strongly support a signaling and/or neuromodulatory role for XA. However, while the parent molecule KYNA is considered as potentially involved in neuropsychiatric disorders because of its inhibitory action on dopamine release in the striatum, the effect of XA on brain dopaminergic activity remains unknown. Here, we demonstrate that acute local/microdialysis-infusions of XA dose-dependently stimulate dopamine release in the rat prefrontal cortex (four-fold increase in the presence of 20 µM XA). This stimulatory effect is blocked by XA-receptor antagonist NCS-486. Interestingly, our results show that the peripheral/intraperitoneal administration of XA, which has been proven to enhance intra-cerebral XA concentrations (about 200% increase after 50 mg/kg XA i.p), also induces a dose-dependent increase of dopamine release in the cortex and striatum. Furthermore, our in vivo electrophysiological studies reveal that the repeated/daily administrations of XA reduce by 43% the number of spontaneously firing dopaminergic neurons in the ventral tegmental area. In the substantia nigra, XA treatment does not change the number of firing neurons. Altogether, our results suggest that XA may contribute together with KYNA to generate a KYNA/XA ratio that may crucially determine the brain normal dopaminergic activity. Imbalance of this ratio may result in dopaminergic dysfunctions related to several brain disorders, including psychotic diseases and drug dependence.

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The orthopedic characterization of cfap298tm304 mutants validate zebrafish to faithfully model human AIS

Scientific Reports ◽

10.1038/s41598-021-86856-1 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Marie-Hardy Laura ◽

Cantaut-Belarif Yasmine ◽

Pietton Raphaël ◽

Slimani Lotfi ◽

Pascal-Moussellard Hugues

Keyword(s):

Cerebrospinal Fluid ◽

Three Dimensional ◽

Fluid Circulation ◽

Micro Computed Tomography ◽

Csf Flow ◽

Cerebrospinal Fluid Circulation ◽

Clinical Criteria ◽

Brain And Spinal Cord ◽

The Brain

AbstractCerebrospinal fluid (CSF) circulation relies on the beating of motile cilia projecting in the lumen of the brain and spinal cord cavities Mutations in genes involved in cilia motility disturb cerebrospinal fluid circulation and result in scoliosis-like deformities of the spine in juvenile zebrafish. However, these defects in spine alignment have not been validated with clinical criteria used to diagnose adolescent idiopathic scoliosis (AIS). The aim of this study was to describe, using orthopaedic criteria the spinal deformities of a zebrafish mutant model of AIS targeting a gene involved in cilia polarity and motility, cfap298tm304. The zebrafish mutant line cfap298tm304, exhibiting alteration of CSF flow due to defective cilia motility, was raised to the juvenile stage. The analysis of mutant animals was based on micro-computed tomography (micro-CT), which was conducted in a QUANTUM FX CALIPER, with a 59 µm-30 mm protocol. 63% of the cfap298tm304 zebrafish analyzed presented a three-dimensional deformity of the spine, that was evolutive during the juvenile phase, more frequent in females, with a right convexity, a rotational component and involving at least one dislocation. We confirm here that cfap298tm304 scoliotic individuals display a typical AIS phenotype, with orthopedic criteria mirroring patient’s diagnosis.

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Characterization of calcium-dependent membrane binding proteins of brain cortex

Biochemical Journal ◽

10.1042/bj2290587 ◽

1985 ◽

Vol 229 (3) ◽

pp. 587-593 ◽

Cited By ~ 14

Author(s):

A R Rhoads ◽

M Lulla ◽

P B Moore ◽

C E Jackson

Keyword(s):

Brain Cortex ◽

Peptide Mapping ◽

Bovine Brain ◽

Particulate Fraction ◽

Structural Homology ◽

One Dimensional ◽

Calcium Dependent ◽

Stokes Radius ◽

The Brain

Proteins of Mr 68 000, 34 000 and 32 000 were selectively extracted by EGTA from brain cortex. The three proteins that were extracted along with calmodulin were acidic, monomeric, and did not exhibit structural homology, as demonstrated by one-dimensional peptide mapping. The Mr-68 000 protein was purified to homogeneity and had a Stokes radius of 3.54 nm and S20,W value of 5.1S. Purified calmodulin, Mr-68 000 protein and two proteins of Mr 34 000 and Mr 32 000, interacted with the brain particulate fraction, with half-maximal binding occurring at 3.5 microM, 8.3 microM and 150 microM-Ca2+ respectively. Proteins were bound independently of each other and calmodulin. Pretreatment of the particulate fraction with trypsin prevented the Ca2+-dependent binding of calmodulin; however, the binding of the Mr-68 000 protein or the Mr−32 000 and −34 000 proteins was unaffected. The Mr-68 000 protein of bovine brain did not cross-react immunologically with Mr-67 000 calcimedin from chicken gizzard.

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