Sensitivity and tolerance to ethanol-induced incoordination and hypothermia in HAFT and LAFT mice

Acute functional tolerance (AFT) manifests as rapid adaptation during a sin gle ethanol exposure, leading to a decrease in the behavioral response to e thanol. In order to investigate the genetic and environmental components of the development of AFT, mice were selectively bred in replicate from HS/Ib g mice. High (HAFT) and low (LAFT) acute functional tolerance selected line s were bred to differ in the rate of development and magnitude of AFT to et hanol's intoxicating effects using a static dowel-balancing task. In the pr esent set of experiments, HAFT and LAFT mice were tested for development of AFT on a fixed-speed rotarod using a protocol similar to that for which th ey were selected. HAFT mice developed greater AFT to ethanol than did LAFT mice. In a separate experiment, other mice from these lines were tested for initial sensitivity and the development of chronic tolerance to ethanol-in duced hypothermia, and ethanol-induced incoordination in the grid test. Pre vious research has detected possible common genetic control of these phenot ypes. No differences between lines were found in initial sensitivity to eth anol or in the development or magnitude of chronic tolerance in either test . These. experiments show that genetic factors influencing the development of acute tolerance to ethanol-induced intoxication are at least partially d istinct from those influencing initial sensitivity and the development of c hronic tolerance to ethanol-induced hypothermia and incoordination. Further more, these experiments show that AFT measured by the stationary dowel gene ralizes to AFT measured by the fixed-speed rotarod. (C) 2001 Elsevier Scien ce Inc. All rights reserved.