[Duration of the narcotic action of nembutal under hyperbarism]

The duration of sleep induced by administration of nembutal in hyperbaric helium-oxygen, nitrogen-oxygen and helium-nitrogen-oxygen mixtures was studied on Wistar rats. Helium reduced the duration of nembutal narcosis. On the contrary, nitrogen increased its duration under high pressure. The most rapid decrease of narcosis was observed with the use of helium-nitrogen-oxygen mixture under the pressure of 40 at. The results of the study are in a good agreement with the theory of the antagonistic effects of helium and nitrogen under high pressure on the central nervous system.