Increased CSF-Levels of Excitotoxic Amino-Acids After Full-Term Perinatal Asphyxia

Abstract

The excitatow am~no-acids (EA. ep. plumate and aswrtate) are believed to k of major importan>e in the path&cnesisz neuronal h i n g e in hyposic-~schem~c bnin iniurv. Studies in immature animal-models of asohvxia have shown an extracellular a~cuhulation EA. The deleterious eficct of EA dn ;he neuron is supported by the fact that the administration of receptor-antagonists is beneficial in esperimenhl models. Agonist-opented receptors arc well developed in the immature human bnin and receptor-density is high in those regions most susceptible to hypouic-ischemic damage. We have examtned the levels of excitatory ammo-acids in full-term asphyctic neonates. Spinal taps were performed in neonates with signs of intrapartum asphyxia (n=10, geshtional age 36-42 w, 0-2 days poslpartal age) and non-aqphyct~c neonates without signs of cerebral diseiae (n=8,GA 29-42 w ,0-13 days postpartum). Amino-acids were analyzed by chromatography (pmolll). Results and conclusions: Aspartate (2.7'3 1.16 vs 0.-0.08) and glutamate (7.92i4.72 vs 1.1% 0.19) dtffercd significantly between asphyctic and nonasphyctic neonates. In the asphyctic group, interindividual differences were high, and further analyris will show tvhelhcr high levels correlate with prognosis or not.