| The N-methyl-D-aspartate receptor (NMDAR) is implicated in neuronal damage caused by hypoxia-ischemia (HI) in immature animals. We investigated the effects of HI on phosphorylation of the NR1 subunit of the NMDAR by protein kinase C and protein kinase A in 7- and 21-day old rats. Our results show that HI caused a reduction in the phosphorylation of NR1 that was followed by differential recovery of phosphorylation at the two ages. We also investigated the possible mechanisms and consequences of the reduced phosphorylation in the older animals. In P21 animals, HI caused a reduction in the association of PKC with SAP102, a component of the NMDAR complex and our preliminary experiments indicated that HI altered the subcellular distribution of PSD proteins. The findings suggest that the age-specific pattern of NR1 phosphorylation after HI might be related to the age-dependent vulnerability of the brain to HI-induced damage. |
