Gl. Schafer et Jc. Crabbe, SENSITIVITY TO ETHANOL-INDUCED ATAXIA IN HOT AND COLD SELECTED LINES OF MICE, Alcoholism, clinical and experimental research, 20(9), 1996, pp. 1604-1612
Studies with inbred strains of mice have suggested that there may be a
genetic correlation between strain sensitivities to the ataxic and hy
pothermic responses to ethanol (EtOH), which would suggest that some g
enes influence both responses. To test this hypothesis, EtOH sensitivi
ty was determined in replicate lines of mice selectively bred for sens
itivity (COLD) or resistance (HOT) to acute ethanol hypothermia. Sever
al tests were used to index ataxia, related traits such as muscle stre
ngth, and locomotor activity. The screen test yielded a dose-dependent
EtOH-induced decrease in performance that did not differ between the
selected lines. Based on the dose-response characteristics of this tas
k, 2.5 g/kg of EtOH was used as the test dose for the remaining experi
ments. Results from the fixed-speed rotarod and the grid test of motor
incoordination also indicated no significant differences between HOT
and COLD mice in sensitivity to EtOH impairment. When the selected lin
es were tested on an accelerating rotarod, COLD mice were impaired by
the acute EtOH injection, but HOT mice were unaffected. COLD mice were
more sensitive to EtOH-induced decrements in grip strength and locomo
tor activity. Overall, the results indicated that HOT and COLD mice we
re only differentially sensitive to EtOH in some tasks related to atax
ia, suggesting that some genes must be associated uniquely with EtOH-i
nduced hypothermia or ataxia. The mixed results from the various tests
indicate that ataxia can best be conceived as a group of related comp
lex behaviors that cannot be assessed adequately by the use of a singl
e task and that ataxia-related behaviors are influenced by different g
roups of genes.