NMDA receptor subunits are phosphorylated by activation of neurotrophin receptors in PSD of rat spinal cord

We have investigated the distribution of NMDA and neurotrophin receptor sys tems and their reciprocal interactions in post-synaptic densities (PSD) pur ified from spinal cord. NMDA receptor subunits, trkA and trkB, but not trkC , were present in spinal cord PSD. The incubation of PSD with BDNF and NGF induced the phosphorylation of NR2A and B subunits. This phosphorylation wa s counteracted by antibodies directed against the catalytic domain of trkA and trkB receptors and by genistein. These results suggest the existence of a previously unexplored cross-talk between neurotrophins and NMDA receptor s in rat spinal cord neurons. NeuroReport 12:1301-1305 (C) 2001 Lippincott Williams & Wilkins.