L-772405 is a selective 5-HT 1D receptor agonist with the K i values of 318, 29 and > 1000 nM aganist guinea pig 5-HT1 B receptor, guinea pig 5-HT 1D receptor and rat 5-HT rransporter, respectively. L-772405 decreases the potassium-induced outflow of 5-HT with an IC 50 value of 240 nM.