Search results for "GABA"

Furosemide interactions with brain GABAA receptors

1997

1. The loop diuretic furosemide is known to antagonize the function of gamma-aminobutyric acid type A (GABAA) receptors. The purpose of the present study was to examine the direct interaction of furosemide with the GABAA receptors by autoradiography and ligand binding studies with native rat and human receptors and with recombinant receptors composed of rat subunits. 2. Autoradiography with [35S]-t-butylbicyclophosphorothionate ([35S]-TBPS) as a ligand indicated that furosemide (0.1-1 mM) reversed the 5 microM GABA-induced inhibition of binding only in the cerebellar granule cell layer of rat brain sections. In all other regions studied, notably also in the hippocampal and thalamic areas, f…

Pregabalin in the Treatment of Refractory Bipolar Disorders

2012

Zvaigžņotā Debess: 2009, Pavasaris (203)

2009

Contents: E.R.Mustel, President of the Astronomical Council of the USSR Academy of Sciences. Congratulations to Editorial Board of “Zvaigžņotā debess” ; Z.Alksne. Gould’s Belt ; I.Daube. At the Radioastrophysical Observatory of the Latvian Academy of Sciences ; Z.Alksne, A.Alksnis. Lopsided Galaxies ; A.Alksnis. HII Region Gum 29 – a Stellar Nursery ; D.Docenko. On Collision of Asteroid 2008 TC3 with the Earth ; V.Lapoška. On „Leap Second” ; I.Vilks, M.Gills. Beginning of the International Year of Astronomy in Paris: Impressions by Latvian Delegates ; J.Jaunbergs. Equatorial Ridge on Iapetus ; M.Sudārs. Space Shuttle Is Not Likely to Retire Next Year ; I.Vilks. Planet Satellite Names in Lat…

Gigantes ecónomicos, enanos políticos

1999

Phasic GABAA-receptor activation is required to suppress epileptiform activity in the CA3 region of the immature rat hippocampus

2012

Summary Purpose:  Despite the consistent observation that γ-aminobutyric acid A (GABAA) receptors mediate excitatory responses at perinatal stages, the role of the GABAergic system in the generation of neonatal epileptiform activity remains controversial. Therefore, we analyzed whether tonic and phasic GABAergic transmission had differential effects on neuronal excitability during early development. Methods:  We performed whole cell patch-clamp and field potential recordings in the CA3 region of hippocampal slices from immature (postnatal day 4–7) rats to analyze the effect of specific antagonists and modulators of tonic and phasic GABAergic components on neuronal excitability. Key Findings…

Control of Programmed Cell Death by Distinct Electrical Activity Patterns

2010

Electrical activity and sufficient supply with survival factors play a major role in the control of apoptosis in the developing cortex. Coherent high-frequency neuronal activity, which efficiently releases neurotrophins, is essential for the survival of immature neurons. We studied the influence of neuronal activity on apoptosis in the developing cortex. Dissociated cultures of the newborn mouse cerebral cortex were grown on multielectrode arrays to determine the activity patterns that promote neuronal survival. Cultures were transfected with a plasmid coding for a caspase-3-sensitive fluorescent protein allowing real-time analysis of caspase-3-dependent apoptosis in individual neurons. Ele…

New Therapeutic Aspects in Fulminant Hepatic Failure

1991

GABAC receptors are functionally expressed in the intermediate zone and regulate radial migration in the embryonic mouse neocortex

2010

Radial neuronal migration in the cerebral cortex depends on trophic factors and the activation of different voltage- and ligand-gated channels. To examine the func- tional role of GABAC receptors in radial migration we ana- lyzed the effects of specific GABAA and GABAC receptor antagonists on the migration of BrdU-labeled neurons in vitro using organotypic neocortical slice cultures. These experi- ments revealed that the GABAA specific inhibitor bicuculline methiodide facilitated neuronal migration, while the GABAC specific inhibitor (1,2,5,6-tetrahydropyridine-4-yl) methylphos- phinic-acid (TPMPA) impeded migration. Co-application of TPMPA and bicuculline methiodide or the unspecific ionot…

Inhibition of GABA and benzodiazepine receptor binding by penicillins.

1980

Penicillins are thought to be GABA receptor antagonists. In order to determine the affinities of various penicillin derivatives for the GABA receptor, their potencies as inhibitors of specific [3H]GABA binding to rat brain membranes were investigated. All investigated penicillins inhibit specific [3H]GABA binding, with IC50 values ranging from 2 to 60 mM. The results are consistent with the assumption that penicillins are weak GABA receptor antagonists.

1-Methyl-?-carboline (Harmane), a potent endogenous inhibitor of benzodiazepine receptor binding

1980

The interaction of several beta-carbolines with specific [3H]-flunitrazepam binding to benzodiazepine receptors in rat brain membranes was investigated. Out of the investigated compounds, harmane and norharmane were the most potent inhibitors of specific [3H]-flunitrazepam binding, with IC50-values in the micromolar range. All other derivatives, including harmine, harmaline, and several tetrahydroderivatives were at least ten times less potent. Harmane has been previously found in rat brain and human urine, so it is the most potent endogenous inhibitor of specific [3H]-flunitrazepam binding known so far, with a several fold higher affinity for the benzodiazepine receptor than inosine and hy…