Abstract 025: Evidence for a Link between Gut Microbiota and Hypertension in the Dahl Rat Model

Abstract

Gut microbiota play a critical role in maintaining physiological homeostasis. This study was designed to evaluate whether gut microbial composition impacts hypertension. 16S rRNA genes obtained from cecal samples of Dahl salt-sensitive (S) and Dahl salt-resistant (R) rats, were sequenced. Bacteria of the phylum Bacteriodetes were higher in the S rats compared with the R rats. Further, the family S24-7 of the phylum Bacteriodetes and the family Veillonellaceae of the phylum Firmicutes were higher in the S rats compared to the R rats. Analyses of the various phylogenetic groups of cecal microbiota revealed significant differences between S and R rats. Both strains were maintained on a high-salt diet, administered antibiotics for ablation of microbiota, transplanted with S or R rat cecal contents and monitored for blood pressure (BP). Systolic BP of the R rats remained unaltered irrespective of S or R rat cecal transplantation. Surprisingly, compared to the S rats given S rat cecal content, systolic BP of the S rats given a single bolus of cecal content from R rats was consistently and significantly elevated during the rest of their life and had a shorter lifespan. Lower level of fecal bacteria of the family Veillonellaceae and increased plasma acetate and heptanoate were features associated with the increased BP observed in the S rats given R rat microbiota compared with the S rats given S rat microbiota. These data demonstrate a link between microbial content and BP regulation and because the S and R rats differ in their genomic composition, provide the necessary basis to further examine the relationship between the host genome and microbiome in the context of BP regulation in the Dahl rats.