Administration of ACTH to suckling rats results in hyperkinetic behavior

The present study on ACTH-administered suckling rats was undertaken to monitor the late behavioral sequelae due to the effects of this drug. The locomotor activity of rats treated with ACTH in the suckling period increased significantly as to the gross size of movements when compared with control rats. The increase in locomotor activity was correlated with the suppression of CNPase activity. These results show that administration of ACTH during the suckling period has suppressive effects on the development of the brain and behavior, and that these effects persist for a longer period after termination of the administration of ACTH than the direct effect of the peptide on endocrine functions.