Abstract:

Objective　To reveal the microRNA (miRNA) profiling of medulla oblongata in spontaneous hypertensive rat (SHR).　Methods　Spontaneous hypertensive rats were taken as the SHR group, and normal blood pressure SD rats were the control group. Microarray analysis was performed to compare the miRNA expression profiles of medulla between the SHR and control group.　Results　Compared with the control group, the systolic pressure of the tail artery of SHR group increased significantly（P<0.0001）. There were significant differential expression profile in the medulla oblongata miRNAs of SHR group, including 16 miRNAs expression up-regulated and 7 miRNAs expression down-regulated (1.5-fold change cutoff, P<0.05). The qRT-PCR data showed that miR-153, miR-193 and miR-301a were significantly down-regulated in medullas of SHRs, which were consistent with the microarray data. From the miRDB online database, we identified 2775 targets for all differentiated miRNAs (target score was set to≥83). The KEGG pathways for these targets were enriched in 12 pathways, including phosphatidylinositide 3-kinase (PI3K) pathway.    Conclusion    miR-153, miR-193 and miR-301a expression are significantly down-regulated in medulla oblongata of spontaneous hypertensive rats. Bioinformatics analysis suggests that nerve inflammation mediated by PI3K pathway may be the main pathogenic pathway regulated by the differentially expressed miRNAs of  hypertension.

Key words: Hypertension, 　MicroRNA, 　Phosphatidylinositide 3-kinase (PI3K) pathway, 　The nerve inflammation