Protective effect of high-dose methylprednisolone on the immature rats with infantile spasms / 国际儿科学杂志

ABSTRACT

Objective Infantile spasms ( IS ) is the most common intractable epileptic encephalopathy during infancy,but there is the lack of animal experiment. By building IS animal model, the study discusses whether high-dose methylprednisolone has the protective effect on the immature rats of infantile spasms. Meth-ods Sprague-Dawley immature rats were randomly assigned to 3 groups on postnatal day 10 ( P10 )control group、model groupⅠand model groupⅡ,thirty rats in each group. Immature rats in model groupⅠand mod-el group Ⅱ were injected NMDA intraperitoneally to induce seizures. The rats in the model groupⅡwere injec-ted intraperitoneally methylprednisolone on postnatal day 11,12 and 13. The clinical behavior of rats were ob-served and recorded. Neuronal apoptosis was detected by TUNEL. Immunohistochemistry and real-time PCR were used to analyze the expression of Bax,Bcl-2,caspase-3 in hippocampus. Results (1)83. 3% of rats in model groupⅠhad seizures,and none of rats in model groupⅡhad seizures on postnatal day 13. (2)The apop-totic cell number of brain tissuesmodel group Ⅱ( 14. 37 ± 2. 02 ) were lower than model group Ⅰ( 25. 67 ± 1. 52)and higher than control group(9. 00 ± 2. 50),the difference was statistically significant(all P<0. 05). (3)Bax protein and mRNA expression levels in model group Ⅱ(44. 55 ± 3. 58,2. 35 ± 1. 01)were lower than model group Ⅰ(58. 05 ± 4. 62,3. 27 ± 0. 95)and higher than control group (28. 90 ± 5. 14,1. 68 ± 0. 50),there was significant difference(all P<0. 05);(4)Caspase-3 expression levels of mRNA in model groupⅡ(5. 99 ± 1. 75) were lower than those in group model group Ⅰ(7. 88 ± 1. 60) and higher than those in control group (3. 60 ± 1. 70),there was significant difference(all P<0. 05). Conclusion High-dose methylprednisolone can reduce NMDA-induced seizures in the IS immature rats. High-dose methylprednisolone has protective effect on the NMDA-induced IS immature rats,which may be relation to weakening seizures and decreasing apoptosis.