A comparison of the effects of the selective 5-HT uptake inhibitor WY 27587 on 5-HT uptake into platelets and synaptosomes in the rat.

N-[( 1-[(6-Fluoro-2-naphthalenyl)methyl]- 4-piperidinyl]amino]carbonyl]-3-pyridine carboxamide (Wy 27587), is 320 times more potent as an inhibitor of the uptake of 5-HT than of the uptake of noradrenaline into synaptosomes from the brain of the rat with a Ki against the uptake of 5-HT of 9.2 +/- 1.4 nM. It was also a potent competitive inhibitor of the uptake of 5-HT in platelets of the rat, with a Ki value of 2.9 +/- 1.5 nM. Ex vivo studies indicated that oral administration of Wy 27587 in the rat caused a prolonged inhibition of the uptake of 5-HT into platelets; inhibition reached a maximum 15 min after administration and the ID50 was 1.5 +/- 0.3 mg/kg.