Neuropediatrics 2006; 37 - THP40
DOI: 10.1055/s-2006-945863

INFLUENCES OF AGE AND THE DURATION OF STATUS CONVULSION ON INTRACELLULAR CYTOCHROME C RELEASE IN HIPPOCAMPUS

L Jiang 1, Y Yuan 1, X Li 1
  • 1Department of Neurology, Children's Hospital, Chongqing University of Medical Science, Chongqing, P.R. China

Objectives: To explore the influences of age and duration of status convulsion SC on intracellular cytochrome C (cytC) release in hippocampus.

Methods: Seizures with duration of 30 minutes or 3 hours were induced in 80 infant and 80 adult Wistar rats (IRs & ARs) with lithium-pilocarpine injected intraperitoneally respectively. The rats were sacrificed at 6 different time points from 3rd hour to 7th day after SC termination. Dynamic change of cytC level in happocampal cells was investigated by flow cytometry.

Results: The level of cytC in happocampal cells was increased in the early stage after 30min SC, and started to decrease 12h later in both IRs and ARs groups. The peak level was reached at 6h after SC, and was 32.47±6.28 in IRs group and 33.23±8.66 in ARs group, both of them were much higher than control groups (P<0.01). At the 7th day after 30min SC, the level of hippocampal intracellular cytC in IRs had decreased to the level of normal control, while the level in ARs was still higher (P<0.05). At the 1st, 3rd, 7th day after SC, the levels of hippocampal intracellular cytC in IRs group wrer obviously lower than ARs group. Compared to the same time point after 30min SC, the levels of hippocampal intracellular cytC after 3h SC were much higher in different age groups. Excluding the effect of the age-related difference, there was the positive correlation between the duration of SC and hippocampal intracellular cytochrome C content by partial correlation analysis r=0.658 p<0.05.

Conclusion: Severe seizure could induce intracellular cytochrome C relase in hippocampums. Age and the duration of SC were the important factors to influence the intracellular cytochrome C relase. The longer the duration of SC was, the higher cytC level was detected. Different from ARs, intracellular release of cytC was sooner inhibited in IRs group after SC, indicated that there could be an internal protected response to inhibit brain damage in premature brain.