Modification of the 5-hydroxytryptophan-induced head-twitch response by exogenous endocrine agents

Estrogens both alone and in combination with progestagens, gonadotrophins, gonadotrophin-releasing factor, corticosteroids, and corticotrophin antagonise the head-twitch response produced by 5-hydroxytryptophan in mice. In contrast, a potentiation was seen following thyroid hormones, thyrotrophin, and thyrotrophin-releasing hormone. Pre-treatment with androgens had no significant effect. Possible mechanisms for these interactions are discussed.