The Cerebral Survival Time of Rabbits in Anoxia Ⅰ. The Development and Evaluation of a Standard Procedure

摘要

1. A method has been developed for the continuous measurement of the anoxic effect on the brain by recording the response of the visual cortex of the rabbit to flashes of light.n2. Shortly after the first cortical reaction to nitrogen breathing the cortical response underwent a marked change. From this point on, it appeared as a nearly monophasic deflection with a consider¬ably higher amplitude than normally. Shortly after anoxic convul¬sions had ceased, the response attained maximal amplitudes (fre¬quently over 200 uv) which gradually declined as the anoxic pro¬gressed.n3. The elapsed time from initiation of nitrogen breathing until the amplitude of the light response had fallen to low levels (20 to no uv) was termed the "cortical survival time" and was used as an index of the anoxic resistance of the animal. This tine aver¬aged 65 seconds compared with 29 seconds for the cessation of rhythmic respiration.