Background:

6,2’-Dihydroxyflavone is a novel antagonist of GABAA receptor.

6,2’-Dihydroxyflavone is a novel antagonist of GABAA receptor. 6,2’-Dihydroxyflavone inhibits [3H]-flunitrazepam binding to the rat cerebral cortex membranes with a Ki of 37.2±4.5 nM. The current elicited with the EC50 concentration of GABA is decreased to 73.6±1.9% of control by co-application of 5 μM 6,2’-Dihydroxyflavone (n=5), compare to a decrease to 65.9±3.0% by 1 μM FG-7142 (n=5). The EC50 for GABA dose response increases from 47.6 to 59.7 μM upon co-application of 5 μM 6,2’-Dihydroxyflavone, and the maximal GABA-current is decreased[1].

6,2’-Dihydroxyflavone-treated mice exhibit significant differences from control mice with respect to the percentage of open arms entries [F(4,73)=8.01, P<0.0001] and the percentage of time spent in open arms [F (4,73)=5.19, P<0.002], but not the number of entries to closed arms [F(4,73)= 0.79,P=0.54]. The post-hoc NewmaneKeuls’ tests confirm that 6,2’-Dihydroxyflavone significantly decreases the percentage of open arm entries and time spent in open arms at the doses of 8 and 16 mg/kg. 6,2’-Dihydroxyflavone treatment similarly increases step-through latency [F(4,75)=4.71, P<0.002], suggesting enhanced cognitive performance[1].

[1]. Wang F, et al. 6,2’-Dihydroxyflavone, a subtype-selective partial inverse agonist of GABAA receptor benzodiazepine site. Neuropharmacology. 2007 Sep;53(4):574-82.