Neuronal Rescue by Refrigeration.

DRUGS; NERVES; MYOCARDIAL infarction; CEREBROVASCULAR disease; CEREBRAL cortex diseases

This article discusses the MK-801 drug which dramatically reduce nerve death in the brains of people after they had suffered a heart attack or stroke. But findings in animals suggest MK-801's usefulness comes not so much from any specific neuroprotective actions as from a simple, drug-induced drop in body temperature. Since the potent drug seems to carry some risks of its own, and simpler ways exist to drop body temperature, the surprising finding has dampened some researchers' hopes for the compound. Scientists say additional research may reveal specific conditions for which the drug has value. Developed by Merck Sharp & Dohme Research Laboratories, MK-801 was about to go into clinical trails for stroke patients in 1989 when John W. Olney and his colleagues at the Washington University School of Medicine reported evidence that the drug itself might damage neurons in the cerebral cortex when given to rats in relatively low doses. Although the risk to humans remained unclear, the findings prompted an indefinite postponement of human testing. Even before those findings, however, various experiments in gerbils and rats had provided disturbingly differing results as to whether the compound actually did or did not enhance neuronal survival.