Genetic background differences between FVB and C57BL/6 mice affect hypnotic susceptibility to pentobarbital, ketamine and nitrous oxide, but not isoflurane.

BACKGROUND: Pharmacogenomics has allowed us to identify the mechanisms underlying much of the inherited variability in drug response. There have been several reports of strain-dependent anesthetic actions in rodents, indicating that significant genetic differences exist in the hypnotic and antinociceptive effects of various anesthetics.
METHODS: Loss of righting reflex was used to compare the hypnotic action of pentobarbital, ketamine, nitrous oxide and isoflurane between two genetically different populations of mice, C57BL/6 with black hair and Friends virus B (FVB) with white hair.
RESULTS: C57BL/6 mice were more susceptible than FVB mice to the hypnotic effects of ketamine, pentobarbital and nitrous oxide. However, the sensitivity to isoflurane did not differ between C57BL/6 and FVB mice.
CONCLUSION: Genetic background affects the hypnotic susceptibility to some anesthetic agents in mice. Our results indicate that there may be a different genetic basis for the operation of hypnosis between isoflurane and other anesthetics, such as pentobarbital, ketamine and nitrous oxide.