Genetic model systems provide a novel approach to understanding
mechanisms of anaesthetic drug action. Many models have been
derived using selection processes that emphasise differential
drug sensitivity, producing animal lines that differ in their
CNS drug response. Studies of vertebrate (rodent) and invertebrate
(Drosophila, Caenorhabditis elegans) animal model systems will
be discussed. Lines can be derived from spontaneous and induced
mutagenic processes, selectively bred lines, inbred lines possessing
inherent differential drug sensitivities and targeted gene knockouts.
The primary focus of the review is the general anaesthetic drugs
that are commonly used in the clinical setting. These agents
include the inhalational agents (halothane, enfurane, isoflurane
and nitrous oxide) and the intravenous induction agents (propofol
and diazepam). Rodent lines with differential sensitivity to
opiates will also be included. Finally, an approach to isolating
and identifying the genes that control anaesthetic sensitivity
will be discussed in a section on mapping quantitative trait loci
(QTL) in recombinant inbred lines