Genetic analysis of anxiety-related behaviors and responses to benzodiazepine-related drugs in AXB and BXA recombinant inbred mouse strains

Recombinant inbred (RI) strains derived from the C57BL/6J and A/J mouse strains were used for behavioral studies designed to estimate the number and location of chromosomal loci responsible for anxiety-related behaviors and differential sensitivity to agonists and inverse agonists of the γ-aminobutyric acid_A (GABA_A)/benzodiazepine receptor complex. The phenotypes of the parental inbred strains and of 28 RI strains were characterized for the number of transitions in the light ⇆ dark exploratory model, anxiolytic response to diazepam, vertical and ambulatory activities in an open field, and sensitivity to the convulsant properties of methyl-β-carboline-3-carboxylate (β-CCM). The strain distribution patterns and estimates of the minimal number of loci obtained for each trait suggest that multiple chromosomal loci contribute to differences in anxiety-related behavioral phenotypes and the behavioral responses to diazepam and β-CCM between C57BL/6J and A/J mice. The best probabilities of linkage were found between the variables characterizing response to diazepam and loci on chromosomes 1 (Xmv-41) and 10 (D10Mit2) and between the sensitivity to the convulsant actions of β-CCM and locus D15Mit5 on chromosome 15.