The Journal of Neuroscience, May 1, 2000, 20(9):3157-3164
Ethanol-Associated Behaviors of Mice Lacking Norepinephrine
David
Weinshenker,
Nicole C.
Rust,
Nicole S.
Miller, and
Richard D.
Palmiter
Howard Hughes Medical Institute and Department of Biochemistry,
University of Washington, Seattle, Washington 98195
Although norepinephrine (NE) has been implicated in animal models
of ethanol consumption for many years, the exact nature of its
influence is not clear. Lesioning and pharmacological studies examining
the role of NE in ethanol consumption have yielded conflicting results.
We took a genetic approach to determine the effect of NE depletion on
ethanol-mediated behaviors by using dopamine
-hydroxylase knockout
(Dbh
/
) mice that specifically lack the ability to synthesize NE. Dbh
/
males have reduced ethanol
preference in a two-bottle choice paradigm and show a delay in
extinguishing an ethanol-conditioned taste aversion, suggesting that
they drink less ethanol in part because they find its effects more
aversive. Both male and female Dbh
/
mice are
hypersensitive to the sedative and hypothermic effects of systemic
ethanol administration, and the sedation phenotype can be rescued
pharmacologically by acute replacement of central NE. Neither the
decreased body temperature nor changes in ethanol metabolism can
explain the differences in consumption and sedation. These results
demonstrate a significant role for NE in modulating ethanol-related
behaviors and physiological responses.
Key words:
norepinephrine; dopamine
-hydroxylase; mice; ethanol; conditioned taste aversion; sedation; hypothermia
Copyright © 2000 Society for Neuroscience 0270-6474/00/2093157-08$05.00/0