CENTRAL INHIBITORY EFFECTS OF CARBON DIOXIDE: I. Felis domesticus

Publisher Website
Google Scholar
Abstract
High concns. of CO2 in O2 increase the frequency but lower the amplitude of the normal cat eeg. The eeg is speeded up by 15% CO2 and 85% O2 but 30% CO2 and 70% O2 slows it (after an initial rise) and causes reversible irregularities to appear. CO2 antagonizes seizures induced by metrazol and by electricity. 30% CO2 is more effective than 20% and this is more effective than 15% and so on down through 5% CO2. The antagonism is present in low and high partial pressures of O2. Hyperventilation, pure O2 and high O2 partial pressures in N2 seem to enhance the convulsive response to electric-shock, whereas low O2 (6%), even without CO2, and 100% N2 shows antagonism to seizure activity. Length of admn. of the gas,mixture and strength of stimulus applied appear to be important factors to consider in addition to concn. of CO2. Utilizing the technique described, the cerebellum does not respond with seizures to electrical stimulation.