[Dynamic changes of the expression of Notch(1) and Jagged(1) in the hippocampus after focal ischemia: experiment with rats].

OBJECTIVE

To detect the expression patterns of Notch(1) and Jagged(1) in the hippocampus of focal ischemia and find out whether the Notch pathway is involved in the regulation of the differentiation of the proliferated neural precursor cells in the dentate gyrus under ischemic conditions.

METHODS

42 SD rats were randomly divided into 3 equal groups: middle cerebral artery occlusion (MCAO) group undergoing MCAO by intraluminal thread technique so as to cause focal cerebral infarction, sham operation group, and normal control group.19 and 28 days after the operation 6 rats in each group were killed with their hippocampus taken out. The protein and mRNA levels of Notch(1) and Jagged(1) in hippocampus were assayed respectively by Western blotting and real-time reverse-transcription PCR.

RESULTS

The protein and mRNA expression levels of Notch(1) on the 19th day of the MCAO group were up-regulated, both significantly higher than those of the sham operation and control groups (all P < 0.05). The protein and mRNA expression levels of Notch(1) on the 28th day of the MCAO group were both significantly lower than those of the same group on the 19th day (both P < 0.01), and were lower than those of the sham operation and control groups on the 28th day, however, not significantly (all P > 0.05). The protein and mRNA expression levels of Jagged(1) on the 19th and 28th days of the MCAO group were significantly higher than those of the sham and control groups (all P < 0.05), however, there were not significant differences in the protein and mRNA expression levels of Jagged(1) on the 19th and 28th days of the MCAO group (all P > 0.05).

CONCLUSION

The protein and gene expression of Notch(1) and Jagged(1) vary dynamically in the hippocampus of focal ischemia, which suggests that the Notch pathway may be a potential mechanism in the regulation of the neurogenesis in the dentate gyrus of hippocampus.