Role of mast cells in pulmonary hypertension with left heart disease

Whole rat genome microarray analyses were performed in lung homogenates of three rats with established PH following supracoronary aortic banding and in three sham-operated controls. Out of a total of 28,000 analysed genes, differential expression defined as 2-fold change with p<0.05 was evident for 120 genes. Of these, 76 were upregulated and 44 downregulated in aortic banding compared with control lungs gene. Enrichment analysis revealed regulation of mast cell specific genes - 13 out of 20 genes were significantly upregulated in aortic banding compared with control lungs. To test for a putative functional role of mast cells in lung vascular remodelling and PH in LHD, we applied a pharmacological approach by treatment of aortic banding rats with the mast cell stabiliser ketotifen. Microarray analysis then compared rats that were treated with untreated.