Circulation, Vol 60, 1600-1605, Copyright © 1979 by American Heart Association
P Scheinberg
The number of patients with cerebral infarctions increases as the
population ages, despite campaigns against hypertension, the greatest risk
factor. Cerebral ischemia initiates events that are presumed to defer the
stage of irreversible injury. These events cause an increase of perfusion
around the central ischemic zone and trigger the Bohr effect, both of which
preserve tissue viability. Almost simultaneously, mitochondrial function
fails, resulting in insufficient energy for the enzyme systems to control
Na and K ion equilibrium. At the same time, protein synthesis slows and
cellular respiratory enzymes decrease their activity, initiating an
irreversible state of tissue change. Tissue fatty acids increase as a
result of dissolution of cell membrane lipoprotein structure. Barbiturates
reduce the extent of experimental infarction. Resperine and aminophylline
are also effective, but there are no corroborative clinical trials. That
ischemic brain damage may be the result of toxic substances in the ischemic
tissue represents a new concept.
ARTICLES
Survival of the ischemic brain: a progress report
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1979 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |