Transcriptomic effects of law salt diet on the mouse left ventricle

Low salt diet is a constant recommendation to hypertensive patients. Here we investigated the impact of prolonged reduced sodium feeding on the geneomic fabrics responsible for heart contraction in adult male mice. Although only 166 (0.59%) of the 27901 quantified transcripts in all samples were significantly up- and 88 (0.32%) down-regulated, the synergistic coupling of the heart contraction genes increased by 22% while their antagonistic coupling decreased by 43%. This substantial remodeling of the heart contraction genomic fabric justifyes the low salt diet recommendation. Agilent mouse two-color gene expression arrays were used to profile the left heart ventricles of 16 weeks old C57Bl/6j male mice subjected for the last 8 weeks of their lives to normal (N, 0.4% Na) or low (L, 0.05%Na) salt diet. Differently labeled biological replicates were cohybridized with each array. Results of similarly labeled different conditions were compared then averaged for the two fluorescent labels. Thus, MW1 & MW3 were compared with MH1 & MH3, MW2 & MW4 were compared with MH2 & + MH4, and the results of the comparisons averaged. This design uses 100% of the resources, has a better normlaiztion and allows all possible comparisons among the conditions.