NMDA R1 MESSENGER-RNA DISTRIBUTION IN MOTOR AND THALAMIC-PROJECTING SENSORY NEURONS IN THE RAT SPINAL-CORD AND BRAIN-STEM

The N-methyl-D-aspartate (NMDA) receptor is important in both sensory and motor neurotransmission. In this study we examine NMDA R1 mRNA hyb ridization signal over individual sensory and motor neurons in the spi nal cord and brain stem, A significantly greater quantity of NMDA R1 m RNA was present in motor neurons of the lumbar spinal cord and hypoglo ssal nucleus compared to thalamic projecting sensory neurons in the sp inal cord dorsal horn, the spinal trigeminal nucleus pars caudalis and the cuneate and gracile nuclei. No significant difference in the quan tity of NMDA R1 mRNA was observed between sensory neurons known to rel ay predominantly nociceptive information (trigeminothalamic and spinot halamic tract neurons) and those that relay predominantly touch and pr oprioceptive information (dorsal column neurons).