372 K. LISSAK, E. ENDROCZl AND E. VINCZE 



4 Xfefr. 0.25 ml. 



2.0 ml ^T 0.25ml. ^ 



Extract Metr. 



Fig. 2. Metrazol convulsion under the influence of previously administered 



brain extract. {Upper channels) — Convulsive activity without brain extract. 



{Lower channels) — Blocking of the convulsive activity after the intravenous 



administration of brain extract (at arrow). 





ImmllM/i'" 



infusion 



Fig. 3. The blocking effect of the brain extract on convulsions induced by 



metrazol in the cat. Bipolar leads from the somatomotor cortex. The arrows 



indicate the administration of brain extract (intravenous). 



before convulsive activity, the intravenous administration of the extract 

 resuhs in a transitory inhibitory effect. An attempt to produce inhibition of 

 a similar nature by the administration of 50-200 mg/kg GABA or GABOB 

 failed. Local apphcation proved to be less effective. However, v^hen it was 

 used the activity due to metrazol convulsion was often replaced by a regular 

 synchronized activity of a frequency of from 2 to 3/sec, which, without the 

 use of the extract, could only be observed very rarely and for a very short 

 time. Even local application of GABA or GABOB failed to influence metrazol 

 activity. 



In the following part of our experiment we examined the effects of GABA, 

 GABOB and the brain extract by recording the superficial negative convulsive 



