Strychnine-sensitive and strychnine-insensitive glycine binding sites in the spinal cord of the wobbler mouse.

Using quantitative autoradiography, the strychnine-sensitive glycine site and strychnine-insensitive glycine site of the N-methyl-D-aspartate receptor were analyzed in the cervical segment of the spinal cord of the wobbler mouse, which is a purported model of human motor neuron diseases. Significantly increased density of the strychnine-sensitive site was found in the lamina II-inner (+17%) and laminae III & IV (+17%) of wobbler mice. The strychnine-insensitive site was also increased in lamina I & II-outer (+15%), lamina II-inner (+15%), laminae III & IV (+48%), laminae V-VIII (+43%) and lamina X (+26%) of wobbler mice. However, no significant differences were observed for the both sites in the ventral horn where motor neurons are located. These findings suggest that both inhibitory and excitatory-associated glycinergic dysfunctions are involved in the wobbler mouse motor neuron disease.