The plasma-occupancy relationship of the novel GABAA receptor benzodiazepine site ligand, alpha5IA, is similar in rats and primates.

Background And Purpose: alpha5IA (3-(5-methylisoxazol-3-yl)-6-[(1-methyl-1,2,3-triazol-4-yl)methyloxy]-1,2,4-triazolo[3,4-a]phthalazine) is a triazolophthalazine with subnanomolar affinity for alpha1-, alpha2-, alpha3- and alpha5-containing GABA(A) receptors. Here we have evaluated the relationship between plasma alpha5IA concentrations and benzodiazepine binding site occupancy in rodents and primates (rhesus monkey).

Experimental Approach: In awake rats, occupancy was measured at various times after oral dosing with alpha5IA (0.