GABAA/benzodiazepine receptor

Salah SM, Jager AK. Two flavonoids from Artemisia herba-alba with in vitro GABAa-benzodiazepine receptor activity. J Ethnopharmacol 2005 99 145-146. 

Risa J, Risa A, Adsersen A, et al. Screening of plants used in southern Africa for epilepsy and convulsions in the GABAA-benzodiazepine receptor assay. J Ethnophar-macol 2004 93 177-182. 

Amino acid neurotransmitter Constituents of hypericum also appear to have effects on amino acid neurotransmission, particularly GABA. Hypericin and a crude extract bind to GABAA and GABAB receptors (Cott 1997). Hyperforin also inhibits synaptosomal GABA reuptake in the low micromolar range (IC50 values of 0.05-0.10 ug/ml). Activity at GABAA benzodiazepine receptors was noted in extracts of four hy-... 

GABAA benzodiazepine j8-carbolines act as inverse agonists of the GABAA benzodiazepine receptor (Mehta and Ticku 1989). Whereas benzodiazepines such as diazepam stimulate Cl- influx, j8-carbolines inhibit it. Harmine, harmaline, harmane, and harmalol inhibit flunitrazepam binding in the micromolar range (half-maximal inhibition between 28 and 130 pM) (Mousah et al. 1986). Endogenous j8-carbolines, such as harmane, have also been found in the human brain, but their endogenous functions are uncertain (Tse et al. 

Richards JG, Schoch P, Haring P, Takacs B, Mohler H. 1987. Resolving GABAA/benzodiazepine receptors cellular and subcellular localization in the CNS with monoclonal antibodies. J Neurosci 7 1866-1886. 

Olanzapine High — serotonin 5-HT2a. 5-HT20 dopamine D-, D2, D3, D4, muscarinic M-, M2, M3, M4, M5, histamine H-, alpha- -adrenergic Weak— GABAa, benzodiazepine receptor, beta-adrenergic... 

Malizia AL, Cunningham VJ, Bell CJ, Liddle PF, Jones T, Nutt DJ (1998) Decreased brain GABAA-benzodiazepine receptor binding in panic disorder. Arch Gen Psychiatry 55 715-720... 

Cantello R, Gianell M, Civardi C, et al Magnetic brain stimulation the silent period after the motor evoked potential. Neurology 42 1951-1959, 1992 Canton T, Doble A Evidence for different binding domains on the GABAa benzodiazepine receptor for benzodiazepines and cyclopyrrolones. Clin Neuro-pharmacol 15 [suppl 1 pt B) 125, 1992... 

Pritchett, D.B., Luddens, H., and Seebnrg, P.H. (1989). Type I and type II GABAA-benzodiazepine receptor prodnced in... 

The GABAA/Benzodiazepine Receptor Complex. The GABAa receptor (125-127) is a transmembrane protein belonging to the superfamily of ligand gated ion channels (128). The receptor consists of five subunits ar-... 

Watt 62), one of the earlier researchers to recognize the potential of African plants in improving mental health, reported the use of Cotyledon orbiculata (Crassulaceae) leaves to treat epilepsy. Again, in vivo studies have demonstrated both aqueous and methanol extracts of C. orbiculata have anticonvulsant properties (moderate protection against pentylenetetrazole, bicuculline, picrotoxin and A-methyl-dl-aspartic induced seizures in mice) 63). However, the ethanolic extract did not show in vitro GABAA-benzodiazepine receptor binding activity 64). 

Rhus dentata Thunb. (leaves) Biflavone. Agathisflavone (100). Extracts of Rhus dentata were not as active as those of Rhus pyroides in the affinity for the GABAa/ benzodiazepine receptor. Svenningsen et al., 2006[132]. 

Figure 6.1 GABAA-benzodiazepine receptor complex showing subunits and binding sites of ligands (binding sites for GABA and BDZ shown O).

Baude A, Sequier J-M, McKernan RM, Olivier KR, Somogyi P (1992) Differential subcellular distribution of the a6 subunit versus the al and /S2/3 subunits of the GABAA/benzodiazepine receptor complex in granule cells of the cerebellar cortex. Neuroscience, 51, 739-748. 

Meinecke DL, Tallman J, Rakic P (1989) GABAA/benzodiazepine receptor-like immunoreactivity in rat and monkey cerebellum. Brain Res., 493, 303-320. 

Liiddens H and Korpi ER (1995). Biological functions of GABAA/benzodiazepine receptor heterogeneity. J Psychiatr Res, 29, 77-94. 

Additionai evidence suggests that the benzodiazepines may diminish voitage-dependent sodium, potassium, and caicium currents in a manner independent of the GABAA/benzodiazepine receptor compiex. 

Fig. 22.17. Ligand interaction with the v-aminobutyric acidA (GABAA)/benzodiazepine receptor complex.

Bassett, M.L., Mullen, K.D., Skolnick, R, and Jones, E.A. 1987. Amelioration of hepatic encephalopathy by pharmacologic antagonism of the GABAA-benzodiazepine receptor complex in a rabbit model of fulminant hepatic failure. Gastroenterology 93 1069-1077. 

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