SLC1A2 and amyotrophic lateral sclerosis: Indeed, excess glutamate has been measured in CSF of ALS patients (Rothstein et al., 1990) and low glutamate uptake in the motor cortex, somatosensory cortex, and spinal cord (Rothstein et al., 1992; Bristol and Rothstein, 1996) have been attributed to the loss of the excitatory amino acid transporter 2 (EAAT2) in motor cortex of ALS patients (Bristol and Rothstein, 1996).