Cerebral pO 2 , pCO 2 and pH: changes during convulsive activity and their significance for spontaneous arrest of seizures.

摘要: SUMMARY The present study on rats and cats aimed to clarify the role played by hypoxia, hypercapnia acidosis in spontaneous arrest of seizures. 1)  In most experiments cortical pO2 declined during seizure activity, whereas pCO2 increased. Occasionally, however, reverse reactions occurred. Since increase blood flow varied over a wide range, it could account for fact that gas tension did not always change same direction or degree seizure. Cessation activity was independent changes tension. 2)  When seizures were arrested experimentally produced spinal neurons showed distinct depolarization. When convulsive discharges suppressed artificial PCO2 units concomitantly hyperpolarized. 3)  When ceased spontaneously, both steep re- hyperpolarization, concomitant fluctuations local tension. The findings lead conclusion hypoxia usually encountered prolonged does reach critical level sufficient depress activity. It must be assumed termination is based, primarily, neuronal processes. RESUME Cette etude se propose de preciser, chez les et chats, le l'hypoxie, l'hypercapnie l'acidose dans l'arret des crises spontanees. 1)  Dans la majorite experiences, Ia au niveau diminue pendant crise, tandis que augmente, quoique occasionnellement, ait observe contraire. La tres grande variabilite l'augmentation circulation sanguine cerebrale pouvait rendre compte du fait une gaz ne changeait pas toujours meme sens ou memes limites. L'arret crise etait independant degre type modifications gaz. 2)  Lorsque etaient arretees suite d'une anoxie provoquee experimentalement, depolarisation neurones corticaux spinaux. Lorsque decharges convulsives supprimees par augmentation artificielle pCO2, parallelement hyperpolarisee. 3)  Lorsque s'arretaient spontanement, cortex moelle montraient rapide repolarisation ensuite hyperpolarisation independamment concomitantes gaz. Ces donnees amenent d'hypoxie d'hypercapnie qu'on habituellement prolongees n'atteint un suffisant pour deprimer l'activite paroxystique. On doit en tirer spontane est dua processus nerveux.