Sensitivity to ethanol-induced motor incoordination in 5-HT1B receptor null mutant mice is task-dependent: Implications for behavioral assessment of genetically altered mice

Neuromuscular impairment by ethanol likely involves complex effects on bala nce, gait, muscle strength, and other features of motor coordination. The p resent experiments showed that relative sensitivity to ethanol-induced moto r impairment in serotonin 1B (5-HT1B) null mutant and control mice was task dependent. We found that ethanol-treated null mutant mice made fewer misst eps on a balance beam than did ethanol-treated wild-type mice, and confirme d a previous finding of their lesser ethanol sensitivity in the grid test. The genotypes did not differ in ethanol sensitivity as measured by the scre en test, static dowel, fixed-speed rotarod, accelerating rotarod, grip stre ngth, or loss of righting reflex tests. These experiments suggest that with in a behavioral domain, alternative tests of function are not equivalent, s o multiple assessment tools should be used to avoid misinterpretation of ge ne function.