[Effect of carbon monoxide and nitric oxide on the apoptosis of hippocampal neurons in rats with febrile seizures].

OBJECTIVE

Febrile seizure (FS) is the most common type of seizure disorders in children. Recurrent FS can cause hippocampal neurons injury. At the same time heme oxygenase/carbon monoxide (HO/CO) system and nitric oxide synthase/nitric oxide (NOS/NO) system were up-regulated and interacted each other. This study examined the effects of the two systems on the apoptosis of hippocampal neurons in rats with recurrent FS.

METHODS

FS was induced in rats by exposure to warm water bath (45.2 degrees C), once every 2 days, 10 times in all. Sprague-Dawley (SD) rats aged 21 days were randomly assigned into four groups: Control (37 degrees C water bath exposure), FS, FS + ZnPP-IX (HO inhibitor) and FS + L-NAME (NOS inhibitor) groups. The apoptosis of hippocampal CA1 neurons was detected by TUNEL.

RESULTS

After recurrent FS, the apoptotic cells in the hippocampal CA1 neurons increased by 225% compared with those in the Control group (P < 0.01). The apoptotic cells in the FS+ZnPP-IX group increased by 62% and 425% compared with those in the FS and the Control groups (both P < 0.01). The apoptotic cells in the FS + L-NAME group decreased by 38% compared with those in the FS group (P < 0.01) and increased by 100% compared with those in the Control group (P < 0.05).

CONCLUSIONS

In recurrent FS, exogenous administration of HO inhibitor ZnPP-IX may induce an increase of apoptotic cells in hippocampal neurons, while NOS inhibitor L-NAME may decrease the apoptotic cells. The results suggest that the HO/CO system might alleviate neuronal damage, while NOS/NO system might augment neuronal damage.