scholarly journals Effects of N(2-propylpentanoyl)urea on hippocampal amino acid neurotransmitters in spontaneous recurrent seizure rats

2010 ◽  
Vol 4 (2) ◽  
pp. 271-279
Author(s):  
Onrawee Khongsombat ◽  
Boonyong Tantisira ◽  
Mayuree H. Tantisira
Keyword(s):  
Amino Acid ◽  
Parent Compound ◽  
Gamma Aminobutyric Acid ◽  
Amino Acid Neurotransmitters ◽  
Recurrent Seizure ◽  
Inhibitory Neurotransmitters ◽  
Spontaneous Recurrent Seizure ◽  
And Control ◽  
Human Temporal Lobe

Abstract Background: N(2-propylpentanoyl) urea (VPU) is a new valproic acid (VPA) analog with higher anticonvulsant activity than its parent compound in various animal models including seizure acutely induced by pilocarpine. Objective: Investigate its effects on hippocampal amino acid neurotransmitters in spontaneous recurrent seizure (SRS) rats. Methods: Pilocarpine hydrochloride was used to induce status epilepticus (SE). Animals were visually observed for two hours/day for an episode of SRS for six weeks. Microdialysis experiment was performed to detect hippocampal amino acid neurotransmitters on those rats that developed SRS. Results: In comparison to normal rats, hippocampal glutamate, gamma-aminobutyric acid (GABA), and glycine, significantly increased in SRS rats. Occurrence of SRS in the faces of increased level of inhibitory neurotransmitters suggests the key role played by glutamate in the genesis and control of SRS. Based on the observation in pilocarpine-induced SE, the level of glutamate in SRS rats significantly decreased by a clinically effective anticonvulsant, VPA (300 and 600 mg/kg, i.p). Similar profile on hippocampal glutamate was also exhibited by VPU (50 and 100 mg/kg, i.p.). Conclusion: The possible role of VPU in controlling seizure in SRS rats and subsequently human temporal lobe epilepsy as VPA was suggested.

Brain amino acid concentrations during diving and acid-base stress in turtles

1985 ◽  
Vol 58 (6) ◽  
pp. 1751-1754 ◽  
Author(s):  
B. M. Hitzig ◽  
M. P. Kneussl ◽  
V. Shih ◽  
R. D. Brandstetter ◽  
H. Kazemi
Keyword(s):  
Amino Acid ◽  
Aminobutyric Acid ◽  
Breath Hold ◽  
Gamma Aminobutyric Acid ◽  
Amino Acid Neurotransmitters ◽  
Acid Base ◽  
Ventilatory Drive ◽  
Amino Acid Concentrations ◽  
Brain Amino Acid

To assess the role of brain amino acid neurotransmitters in the breath hold of diving animals, concentrations of free amino acids present in the brains of turtles immediately after 2 h of apneic diving (at 20 degrees C) were measured. Additionally, the same measurements were performed on four other groups of animals subjected to 2 h of hypercapnia (8% CO2 in air), anoxia (N2 breathing), anoxia plus hypercapnia (8% CO2–92% N2), or air breathing (control). Significant changes in the concentrations of the inhibitory amino acid neurotransmitters known to affect respiration [gamma-aminobutyric acid (GABA) and taurine] were seen. GABA increased significantly in those animals subjected to anoxia, whereas taurine decreased significantly in the diving animals and increased significantly in those subjected to anoxia plus hypercapnia. These results suggest that the attenuated central ventilatory drive during diving in these animals may be related to alterations in brain concentrations of GABA and taurine.

scholarly journals Techniques to optimize post-embedding single and double staining for amino acid neurotransmitters.

1992 ◽  
Vol 40 (7) ◽  
pp. 1011-1020 ◽  
Author(s):  
K D Phend ◽  
R J Weinberg ◽  
A Rustioni
Keyword(s):  
Electron Microscopy ◽  
Amino Acid ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Double Staining ◽  
Amino Acid Neurotransmitters ◽  
Simultaneous Visualization

We report a number of technical refinements for single and double staining with post-embedding electron microscopy for glutamate, aspartate, and gamma-aminobutyric acid. Best results were obtained with 2.5% glutaraldehyde in the fixative and by minimizing the duration of plastic polymerization and the interval between cutting and reacting. Quantitative documentation of the ability of exogenous glutamate, aspartate, and gamma-aminobutyric acid to block their immune staining is provided. Increased intensity of staining with the glutamate and aspartate antisera resulted from preincubation of glutamate antiserum with aspartate and aspartate antiserum with glutamate. To perform double staining with antisera raised in the same species, it was necessary to block antigenicity of the first antiserum; best results were obtained with hot paraformaldehyde fumes. By using a detergent instead of etching, these methods permitted the simultaneous visualization of tracers to identify neuroanatomic pathways.

The chronic effect of pulsed 1800 MHz electromagnetic radiation on amino acid neurotransmitters in three different areas of juvenile and young adult rat brain

2018 ◽  
Vol 34 (12) ◽  
pp. 860-872
Author(s):  
Nawal A Ahmed ◽  
Nasr M Radwan ◽  
Heba S Aboul Ezz ◽  
Yasser A Khadrawy ◽  
Noha A Salama
Keyword(s):  
Amino Acid ◽  
Young Adult ◽  
Electromagnetic Radiation ◽  
Mobile Phone ◽  
High Performance ◽  
Gamma Aminobutyric Acid ◽  
Amino Acid Neurotransmitters ◽  
Adult Rats ◽  
Mobile Phone Use ◽  
Neurological Effects

The extensive use of mobile phones worldwide has raised increasing concerns about the effects of electromagnetic radiation (EMR) on the brain due to the proximity of the mobile phone to the head and the appearance of several adverse neurological effects after mobile phone use. It has been hypothesized that the EMR-induced neurological effects may be mediated by amino acid neurotransmitters. Thus, the present study investigated the effect of EMR (frequency 1800 MHz, specific absorption rate 0.843 W/kg, power density 0.02 mW/cm2, modulated at 217 Hz) on the concentrations of amino acid neurotransmitters (glutamic acid, aspartic acid, gamma aminobutyric acid, glycine, taurine, and the amide glutamine) in the hippocampus, striatum, and hypothalamus of juvenile and young adult rats. The juvenile and young adult animals were each divided into two groups: control rats and rats exposed to EMR 1 h daily for 1, 2, and 4 months. A subgroup of rats were exposed daily to EMR for 4 months and then left without exposure for 1 month to study the recovery from EMR exposure. Amino acid neurotransmitters were measured in the hippocampus, striatum, and hypothalamus using high-performance liquid chromatography. Exposure to EMR induced significant changes in amino acid neurotransmitters in the studied brain areas of juvenile and young adult rats, being more prominent in juvenile animals. It could be concluded that the alterations in amino acid neurotransmitters induced by EMR exposure of juvenile and young adult rats may underlie many of the neurological effects reported after EMR exposure including cognitive and memory impairment and sleep disorders. Some of these effects may persist for some time after stopping exposure.

Role of solitarial GABAergic mechanisms in control of swallowing

1991 ◽  
Vol 261 (3) ◽  
pp. R639-R646 ◽  
Author(s):  
Y. T. Wang ◽  
D. Bieger
Keyword(s):  
Pattern Generator ◽  
Chemical Stimulation ◽  
Tonic Inhibition ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Esophageal Peristalsis ◽  
Muscarinic Agonists ◽  
And Control ◽  
Stimulation Of

The role of solitarial gamma-aminobutyric acid (GABA)-ergic mechanisms in deglutition was investigated in urethane-anesthetized rats. When applied to the dorsal extraventricular surface of the nucleus tractus solitarii (NTS), muscimol reversibly inhibited 1) buccopharyngeal swallows evoked by either electrical or chemical stimulation of the NTS and 2) esophageal peristalsis evoked by muscarinic agonists. Bicuculline (5-1,000 pmol) applied to the NTS surface evoked rhythmic swallowing, which was reversibly blocked by DL-2-amino-7-phosphonoheptanoic acid (5-500 pmol). Methscopolamine (5-100 pmol) applied at the same site abolished the esophageal component of the response. Intrasolitarial application of bicuculline at s-glutamate-responsive loci in the intermediate and central subnuclei gave rise to buccopharyngeal and esophageal responses, respectively, and to a concomitant facilitation of glutamate-evoked responses. In subliminal doses ejected at esophageal loci, bicuculline induced deglutitive esophageal peristalsis during elicitation of buccopharyngeal swallowing by chemical (kainate or norepinephrine) or electrical stimulation of the NTS. We conclude that solitarial GABA neurons exert a tonic inhibition of the medullary deglutitive pattern generator and control buccopharyngeal-esophageal coupling.

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