6,2'-二羟基黄酮

GABA _A receptor

6,2'-Dihydroxyflavone is a novel antagonist of GABA _A receptor. 6,2'-Dihydroxyflavone inhibits [ ³ H]-flunitrazepam binding to the rat cerebral cortex membranes with a K _i of 37.2±4.5 nM. The current elicited with the EC ₅₀ 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 EC ₅₀ 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.

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.