6,2'-Dihydroxyflavone

Cell experiment:

Membranes from HEK 293T cell are used in this study. Briefly, aliquots of membranes are incubated with 1 nM [3H]-flunitrazepam or 8 nM [3H]-Ro15-4513 at 4°C for 90 min in the presence or absence of 6,2'-Dihydroxyflavone. After incubation, the mixtures are filtered onto Whatman GF/B filters with a Brandel 24-well harvester. Each filter is incubated for at least 1 h with 4 mL scintillation cocktail before measurement of radioactivity in a Beckman-Coulter LS 6500 scintillation counter. For saturation analysis, the membranes are incubated with increasing concentrations of [3H]-flunitrazepam or [3H]-Ro15-4513. Binding affinity is determined by nonlinear regression analysis[1].

Animal experiment:

Male ICR mice are randomized into six groups (n=12 to 16/group), and receive 0.4 mg/kg scopolamine (i.p.) 45 min prior to training, followed with vehicle (dd water, pH 9.0, p.o.), 2, 4, 8 or 16 mg/kg 6,2'-Dihydroxyflavone (p.o.), or 30 mg/kg FG-7142 (i.p.) 30 min prior to training. On the training trials, each mouse is placed into the lighted chamber of a two-compartment box, and the door leading to the dark chamber is opened 10 s later. Once the mouse enters the dark compartment, the door is closed and an inescapable electric foot-shock (0.4 mA, 1 s) is delivered from the grid floor. The mouse is removed from the apparatus 10 s later. The step-through latency is recorded, with the cut-off step-through latency set at 300 s[1].

References:

[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.