Alteration in amino acids in motor neurons of the spinal cord in amyotrophic lateral sclerosis

Little is known concerning the changes of amino acid composition in differe nt regions of the spinal cord in patients with amyotrophic lateral sclerosi s (ALS). We performed quantitative amino acid analyses in the posterior fun iculus, the lateral corticospinal tract, and the anterior horn of cervical enlargement of the spinal cord from seven ALS patients? and the results wer e compared with those of seven patients with other neurologic diseases (con trol A) and seven patients without neurologic diseases (control B). The lev els of collagen-associated amino acids, hydroxyproline, proline, glycine, a nd hydroxylysine, were markedly lower in the lateral corticospinal tract an d the anterior horn of ALS patients than in controls A and B. The contents of the acidic amino acids glutamate and aspartate were also significantly d ecreased in the lateral corticospinal tract and the anterior horn of ALS pa tients as compared with those of controls A and B. These data suggest that decreased contents of collagen-associated amino acids and excitatory amino acids are related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS. (C) 1999 Elsevier Science B.V. All rights reserv ed.