Activation of a Cortical Seizure Focus Under Hypoxia: O2-Deficiency Effect or Result of Tissue Acidosis?
The influence of O2 deficiency on cerebral convulsions was examined many times before (4, 5, 6). A suppression of the convulsion activity was observed. We studied the effects of hypoxia on a cortical seizure focus. Under moderate hypoxia different results were obtained: the frequency of focal cortical seizure discharges even increased. At first we presumed a direct hypoxic stimulation of the focus. In further tests animals were exposed to hypercapnic conditions. The comparison of results of these various test series led to the conclusion that focus activation recorded under hypoxia is not an effect pertaining immediately to O2 deficiency but the consequence of tissue acidosis induced by hypoxia.
KeywordsModerate Hypoxia Hypercapnic Acidosis Hypoxia Period Tissue Acidosis Focal Discharge
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