Search results for "Muscimol"

Kavapyrone enriched extract fromPiper methysticum as modulator of the GABA binding site in different regions of rat brain

1994

Regional differences in the modulation of [3H] muscimol binding to GABAA receptor complexes by kavapyrones, compounds of the rhizome of the plant Piper methysticum which possess sedative activity, were demonstrated using membrane fractions obtained from target brain centers of kavapyrone action: hippocampus (HIP), amygdala (AMY) and medulla oblongata (MED), and from brain centers outside the main kavapyrone effects as frontal cortex (FC) and cerebellum (CER). The kava extract enhanced the binding of [3H] muscimol in a concentration-dependent manner with maximal potentiation of 358% over control in HIP followed by AMY and MED (main target brain centers). Minimal stimulation was observed in C…

GABA-A Receptors Regulate Neocortical Neuronal Migration In Vitro and In Vivo

2006

The cortical migration process depends on a number of trophic factors and on the activation of different voltage- and ligand-gated channels. We investigated the role of gamma-aminobutyric acid (GABA) type A receptors in the neuronal migration process of the newborn rat parietal cortex in vivo and in vitro. Local in vivo application of the GABA-A antagonist bicuculline methiodide (BMI) or the agonist muscimol via cortical surface Elvax implants induced prominent alterations in the cortical architecture when compared with untreated or sham-operated controls. BMI- and muscimol-treated animals revealed heterotopic cell clusters in the upper layers and a complete loss of the cortical lamination …

Multivariate optimization of the hollow fibre liquid phase microextraction of muscimol in human urine samples.

2016

Abstract A liquid phase microextraction based on hollow fibre followed by liquid chromatographic determination was developed for the extraction and quantitation of the hallucinogenic muscimol from urine samples. Method applicability on polar hallucinogens was also tested on two alkaloids, a psychedelic hallucinogen, tryptamine and a polar amino acid, tryptophan which exists in its charged state in the entire pH range. A multivariate design of experiments was used in which a half fractional factorial approach was applied to screen six factors (donor phase pH, acceptor phase HCl concentration, carrier composition, stirring rate, extraction time and salt content) for their extent of vitality i…

Comparative Study of Different Column Types for the Separation of Polar Basic Hallucinogenic Alkaloids

2016

The number of hallucinogenic compounds that have been separated simultaneously by liquid chromatography is limited. This research aimed to identify a column(s) that can allow for separation of several hallucinogens. The extent of separation of seven polar hallucinogenic tryptamine and phenethylamine derived alkaloids containing a basic N atom that becomes protonated at low pH values were investigated on five reverse-based columns and one hydrophilic interaction liquid chromatography (HILIC) column. An RP-phenyl and a negatively charged fused core HILIC were identified and recommended as effective columns in this regard. This research is the first to introduce a HILIC column in separation of…

Alcheimera slimības modelēšana žurkām ar streptozotocīna intracerebroventrikulāro ievadīšanu

2015

Šī darba mērķis bija izveidot žurku STZ icv AD-tipa modeli un pārbaudīt GABAA agonista muscimola mazo devu (0,01 un 0,05 mg/kg) ietekmi uz iemācīšanos un atmiņu ūdens labirinta testā. Rezultāti rāda, ka: a) Abās MUSC-aCSF grupās izbēgšanas latence treniņdienu laikā samazinājās līdzīgi kontrolei; efekti saglabājās arī gala testā; b) Abās MUSC-STZ grupās izbēgšanas latence treniņdienās būtiski samazinājās pret Sal-STZ (p<0,0001), un gala testā būtiski pieauga platformas zonas šķērsošana un laiks platformas kvadrantā pret Sal-STZ (p<0,0001). Šie dati liecina, ka STZ icv ievade spēj ietekmēt AD-tipa agrīnos kognitīvos traucējumus un muscimols spēja tos reversēt caur GABA aktivēšanos. GABAerģisk…

Rapid determination of ibotenic acid and muscimol in human urine

2014

Neirotrofo faktoru ekspresija streptozocīna - Alcheimera slimības modelī ar muscimolu

2016

1906. gadā vācu psihiatrs un neiropatologs Aloīzs Alcheimers pirmo reizi aprakstīja 56 gadu vecumā mirušu pacienti, kura mira neskaidras slimības dēļ, pēdējo četru gadu laikā strauji zaudējot atmiņu un dažādas iemaņas. Laika gaitā, analizējot medicīniskos pierakstus un pētot mirušās pacientes smadzenes, tika noteikta amiloīdo plātņu un neirofibrilāro mezglu esamība smadzenēs, kas tika nosaukta par Alcheimera slimību (Engstrom, 2007). Alcheimera slimība ir progresējoši smadzeņu darbības traucējumi, kā rezultātā smadzenes pakāpeniski „noārdās”. Visbiežāk tā rodas cilvēkiem 65-70 gadu vecumā. Slimības attīstības gaitā attīstās negatīvas izmaiņas atmiņā, domāšanā, dažādās darbībās un uzvedībā, …

Multivariate optimization of the hollow fibre liquid phasemicroextraction of muscimol in human urine samples

2016

A liquid phase microextraction based on hollow fibre followed by liquid chromatographic determinationwas developed for the extraction and quantitation of the hallucinogenic muscimol from urine samples.Method applicability on polar hallucinogens was also tested on two alkaloids, a psychedelic hallucinogen,tryptamine and a polar amino acid, tryptophan which exists in its charged state in the entire pH range. Amultivariate design of experiments was used in which a half fractional factorial approach was applied toscreen six factors (donor phase pH, acceptor phase HCl concentration, carrier composition, stirring rate,extraction time and salt content) for their extent of vitality in carrier media…

Effects of ovariectomy and steroid replacement on GABAA receptor binding in female rat brain.

1991

Abstract The specific binding of tritiated muscimol to γ-aminobutyric acid (GABA) receptor sites was studied in distinct brain areas of female rats during different endocrine states. In diestrous rats with intact ovaries the highest receptor densities were found in the cortex (10.24 pmol/mg protein) and the lowest concentrations in the mediobasal hypothalamus (3.29 pmol/mg protein). Four weeks after removal of the ovaries, the number of binding sites was enhanced up to 2.4-fold in all brain areas investigated: the preoptic brain area, mediobasal hypothalamus, corticomedial amygdala, and cerebral cortex. The affinity of the binding sites remained unchanged. Substitution of estradiol and prog…

gamma-Aminobutyric acid and cholinergic transmission in the guinea-pig ileum.

1983

1. The effects of GABA on release of acetylcholine and on contractility of the smooth muscle were studied in the myenteric plexus-longitudinal muscle preparation of the guinea pig. Acetylcholine was determined as radiolabelled transmitter from strips preloaded with 3H-choline. 2. GABA (1–300 μM) caused an increase in resting tension of smooth muscle as well as an increase in release of acetylcholine that was considerably reduced by tetrodotoxin. The facilitation by GABA of acetylcholine release exhibited a marked tachyphylaxis. The increase in muscle tension was clearly related to the increase in acetylcholine release. Muscimol (0.1–10 μM) also enhanced the release of acetylcholine. The eff…