Short Communication New 5-HT1A receptor antagonist: [3H]p-MPPF

A new 5-HT_1A receptor antagonist ligand, [³H]p-MPPF, 4-(2′-methoxy-)-phenyl-1-[2′-(N-2′-pyridyl)-p-fluorobenzamido]ethyl-piperazine, was prepared and characterized. It demonstrated high affinity and selectivity toward 5-HT_1A receptors (K_d = 0.34 ± 0.12 nM and B_max = 145 ± 35 fmol/mg protein in rat hippocampal membrane homogenates). The binding is not sensitive to 100 μM Gpp(NH)p. Initial autoradiography studies of rat brain sections exhibit regional localization consistent with the known 5-HT_1A receptor distribution. This potential 5-HT_1A antagonist ligand may provide a powerful tool for 5-HT_1A receptor pharmacology studies in the central nervous system. © 1996 Wiley-Liss, Inc.