Studies on 5-Hydroxytryptamine and 5-Hydroxytryptophan

Abstract

The 5-HT content and the 5-HTP decarboxylase activity of several tissues of seven mammalian species has been estimated. Whereas 5-HT is concentrated in the spleen and gastrointestinal tract, the highest enzyme activity is found in the kidney, liver, gut and brain. In rats, treatment with reserpine or chlorpromazine lowers the 5-HT content of many tissues and reduces the 5-HTP decarboxylase activity of the kidney, but prolonged treatment with cortisone only lowers the 5-HT content of the skin.