Influence of haloperidol on ACTH and beta-endorphin secretion in the rat

The injection of haloperidol, a dopamine receptor blocker, was followed by a large increase of plasma ACTH and beta-endorphin-like immunoreactivity (beta-EI) in the rat. This effect was prevented when the rats were previously treated with corticosteroids. These results suggest that catecholamines inhibit ACTH and beta-endorphin secretion in the rat.