Excitatory And Inhibitory Amino Acids
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. Psicolatina : caracterização conformacional e avaliação do efeito sobre os níveis de aminoácidos excitatórios e inibitórios em regiões cerebrais de roedores / Psychollatine : conformational characterization and evaluation of the effects on the excitatory and inhibitory amino acids levels in brain regions of rodents
A avaliação química das folhas de Psychotria umbellata levou a identificação de quatro alcalóides pertencente ao grupo dos indol monoterpenos glicosilados, sendo psicolatina a substância majoritária. Em estudos subseqüentes, psicolatina apresentou importantes efeitos farmacológicos provavelmente relacionados com a modulação de receptores opióide
Publicado em: 2008
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2. Distinct muscarinic receptors inhibit release of gamma-aminobutyric acid and excitatory amino acids in mammalian brain.
Intracellular recordings were made from neurons of rat lateral amygdala, nucleus accumbens, and striatum in vitro. Synaptic potentials mediated by gamma-aminobutyric acid and by excitatory amino acids were isolated pharmacologically by using receptor antagonists, and their amplitudes were used as a measure of transmitter release. Muscarine and acetylcholine
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3. Whole-cell current noise produced by excitatory and inhibitory amino acids in large cerebellar neurones of the rat.
1. Membrane noise and current changes produced by glutamate and related excitatory amino acids have been examined in cultured large cerebellar neurones (including Purkinje cells), with whole-cell patch-clamp methods. The sensitivity of these neurones to the inhibitory amino acids gamma-aminobutyric acid (GABA) and glycine has also been studied. 2. The neuron
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4. Amino acid receptors of midget and parasol ganglion cells in primate retina.
Primate retinas contain two major ganglion cell types. Midget (or P type) cells have relatively sustained responses to light; the amplitude and polarity of these responses vary with stimulus wavelength. Parasol (or M type) cells are more sensitive to stimulus contrast and respond more transiently but are not selective for color. Both types can be further sub
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5. Excitatory amino acid-receptor-mediated EPSPs in rat dorsolateral septal nucleus neurones in vitro.
1. Intracellular recordings were made from rat dorsolateral septal nucleus (DLSN) neurones in vitro. We investigated depolarizations resulting from pressure application of excitatory amino acids and compared these to synaptically evoked excitatory postsynaptic potentials (EPSPs). 2. EPSPs evoked by focal fimbrial afferent stimulation in saline with 30-50 mic
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6. Effects of excitatory amino acids and their antagonists on membrane and action potentials of cat caudate neurones.
The electrical activity of caudate neurones was recorded with intracellular electrodes in halothane anaesthetized cats. Agonists and antagonists of excitatory amino acid receptors were applied by micro-ionophoresis and their effects on membrane- and action potentials and on cortically evoked synaptic potentials evaluated. The agonists, L-aspartate (asp), L-g
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7. Ia afferent excitation of motoneurones in the in vitro new-born rat spinal cord is selectively antagonized by kynurenate.
Intracellular recordings from motoneurones in in vitro preparations of new-born rat spinal cord were used to study the sensitivity of the Ia excitatory post-synaptic potential (e.p.s.p.) to antagonists of excitatory amino acids, in order to test whether group Ia primary afferents release L-glutamate, or a similar compound, as a neurotransmitter. The Ia e.p.s
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8. Active transport of gamma-aminobutyric acid and glycine into synaptic vesicles.
Although gamma-aminobutyric acid (GABA) and glycine are recognized as major amino acid inhibitory neurotransmitters in the central nervous system, their storage is poorly understood. In this study we have characterized vesicular GABA and glycine uptakes in the cerebrum and spinal cord, respectively. We present evidence that GABA and glycine are each taken up
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9. Neuroendocrine mechanism of onset of puberty. Sequential reduction in activity of inhibitory and facilitatory N-methyl-D-aspartate receptors.
In humans and in several animal species, puberty results from changes in pulsatile gonadotropin-releasing hormone (GnRH) secretion in the hypothalamus. In particular, the frequency of pulsatile GnRH secretion increases at the onset of puberty, as can be shown by using hypothalamic explants of male rats of 15 and 25 d. Previous observations from us and others
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10. GABA and glutamate mediate rapid neurotransmission from suprachiasmatic nucleus to hypothalamic paraventricular nucleus in rat.
1. Intracellular sharp electrode and whole-cell patch-clamp recording from characterized paraventricular nucleus (PVN) neurones in rat hypothalamic slices were used to study the synaptic mechanism and associated neurotransmitters that mediate their response to suprachiasmatic nucleus (SCN) stimulation. 2. Electrical stimulation restricted to SCN evoked short
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11. Membrane properties and synaptic potentials of three types of neurone in rat lateral amygdala.
1. Intracellular recordings were made from the lateral nucleus of the amygdala in tissue slices cut from rat brain and maintained in vitro. 2. Three types of neurones were distinguished according to the after-potential that followed an action potential. Type 1 cells (44%, n = 225) had depolarizing after-potentials, resulting from a calcium-dependent chloride
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12. Electrophysiological properties of rat CA1 pyramidal neurones in vitro modified by changes in extracellular bicarbonate.
1. Intracellular recordings were made from the somata of CA1b hippocampal pyramidal neurones in vitro and the concentration of bicarbonate ion ([HCO3-]o) in the artificial cerebrospinal fluid (ACSF) was varied by substitution for Cl-. 2. Reducing [HCO3-]o from 26 mM (standard ACSF) to 8.6 mM or raising it to 72 mM had only minor effects on resting membrane p