Investigation of the effect of chlorophenothane and certain chemically related compounds on the cerebral gamma-aminobutyric acid contents in rats.

The effect of chlorophenothane (pp'--DDT) and five structurally related compounds op-DDD (op'-DDD, pp'-DDD, DTE, DCMP and DCP see text) on the cerebral hemisphere gamma-aminobutyric acid (GABA), the main inhibitory transmitter in brain contents and possible correlation with central activities was demonstrated in rats. The tested compounds were given in oral doses of 600 mg/kg in peanut oil. Cerebral GABA content was determined 1, 3 and 6 hrs after the ingestion of pp'-DDT and 3 hrs after each of the other drugs. The mean GABA content in each group of rats was compared with control groups, either without any treatment, or receiving the equivalent volume of peanut oil. pp'-DDT produced a significant reduction in brain GABA contents 3 and 6 hrs after its administration. This was accompanied by excitability, tremor and clonic convulsions. Of the congenors, only DTE exerted a similar effect. The present results point to the possibility of partial involvement of GABA in the tremor and convulsions induced by pp'-DDT. They also indicate the importance of the CCl2 grouping in the molecule for the induction of central effects of pp'-DDT.