UCLA Brain Scientists
Crack Mystery Of How Alcohol Causes Intoxication
February 20, 2005
with how brain cells communicate with one another,
coordination, grogginess, impaired memory and loss of
inhibitions associated with drunkenness. Yet researchers
have been unable to pinpoint how alcohol causes this
disruption in the brain.
Now scientists at the David Geffen
School of Medicine at UCLA have deciphered how a naturally
occurring gene mutation in rats' brains lowers the
animals' tolerance to alcohol, leading to rapid and acute
intoxication after the equivalent of one drink. The UCLA
study is the first to identify how the gene variation
alters GABA receptors -- specific sites targeted by
chemicals from the brain cells -- making them more
responsive to very low levels of alcohol. Alcohol enhances
the GABA receptors' influence on brain cells, slowing the
cells' activity and ability to communicate.
The fact that the gene mutation
arises naturally suggests that tolerance levels to alcohol
may be genetically wired in people, too. If so, the
findings could eventually help identify children and
adults at higher risk of developing alcohol dependency, so
these individuals can make an informed decision about
whether to drink. The study results may also speed the
development of new drugs that target alcohol-sensitive
GABA receptors, leading to better treatments for alcohol
poisoning and addiction.
Authors of the study include UCLA
Brain Research Institute members Richard Olsen, Ph.D.,
professor of molecular and medical pharmacology; Thomas
Otis, Ph.D., associate professor of neurobiology; and
Martin Wallner, Ph.D., pharmacology researcher.
The Feb. 6 online edition of Nature
Neuroscience reports the findings.
The National Institute of
Neurological Disorders and Stroke and the National
Institute of Alcohol Abuse and Addiction supported the