Does alcohol kill brain cells?
Q: Just wondering, are brain cells really
killed when alcohol is consumed? (Billy,
World)
 Swirls
and fissures of the human cortex. Photo courtesy of Marymount College.
A: No, usually brain cells are not
killed. For 16 years, Roberta J. Pentney, professor of anatomy and cell biology
at the University at Buffalo, has studied chronic alcohol abuse and brain
function. She concludes that alcohol does not kill brain cells but rather
damages dendrites--the branched ends of nerve cells that bring messages into the
cell.
Alcohol surely affects the brain, as we all know, causing
slurred speech, clumsiness, slow reflexes, and a loss of inhibition. But alcohol
doesn't destroy the brain cells to cause these problems.
Rather, alcohol dilates the channels in the cellular structure
that regulates the flow of calcium. More calcium than normal flows into the
cells and stimulates increased activity. Somehow this abnormal "turning on" of
activity causes a loss of the end segments but does not kill the whole cell.
Losing the end segments, however, means losing incoming messages, which disrupts
brain function.
The good news is: the damage to the brain cells, for the most
part, isn't permanent. The brain repairs itself but the recovery process does
change nerve-cell structure. So most function returns to normal but some does
not.
Another researcher, working independently finds similar
results: Alcohol doesn't kill brain cells; instead it slows communications.
Richard Gross, professor of medicine, chemistry, and molecular biology and
pharmacology at Washington University in St. Louis, discovers alcohol combines
with the brain's fatty acids and forms compounds called fatty-acid-ethyl esters.
These compounds, in turn, change the flow of electric and chemical signals in
the brain. A change in this flow alters how the brain works.
A molecule of fatty-acid-ethyl ester latches onto and enters a
nerve cell. Inside the cell, the compound speeds up a release of potassium ions,
which inhibits the release of neurotransmitters, and that slows down
communication between cells.
A drink doesn't kill brain cells. It damages the way brain
cells communicate and the damage is largely reversible.
Further Surfing:
Does marijuana kill brain cells? WonderQuest
Purkinje neuron, how alcohol damages brain, Roberta J. Pentney,
University at Buffalo, 1-Dec-99
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