Talnetant (SB 223412) is a selective, competitive, brain-penetrant NK3 receptor antagonist with the ability to modulate mesolimbic and mesocortical dopaminergic neurotransmission

Talnetant competitively antagonized neurokinin B (NKB)-induced responses at the human recombinant receptor in both calcium and phosphoinositol second messenger assay systems (pA2 of 8.1 and 7.7, respectively).?In guinea pig brain slices, talnetant antagonized NKB-induced increases in neuronal firing in the medial habenula (pKB = 7.9) and senktide-induced increases in neuronal firing in the substantia nigra pars compacta (pKB = 7.7) with no diminution of maximal agonist efficacy, suggesting competitive antagonism at native NK3 receptors.?Talnetant (3-30 mg/kg i.p.) significantly attenuated senktide-induced 'wet dog shake' behaviors in the guinea pig in a dose-dependent manner.?Microdialysis studies demonstrated that acute administration of talnetant (30 mg/kg i.p.) produced significant increases in extracellular dopamine and norepinephrine in the medial prefrontal cortex and attenuated haloperidol-induced increases in nucleus accumbens dopamine levels in the freely moving guinea pigs[1].