Fig. 2
From: Distinct expression patterns of HCN channels in HL-1 cardiomyocytes
Expression of hcn genes in HL-1 cell samples obtained at different culture densities. Gene expression levels were determined via qPCR on cDNA from HL-1 cells propagated at different culture densities according to cultivation strategy (i). Quantification of genes (y-axis) is shown in relation to culture confluency (x-axis). Values for hcn1 (a), hcn2 (b), and hcn4 (c) were normalized to gapdh (see 2.3.). Samples were grouped according to visually determined culture densities. Grey inlays denote conditions where HL-1 cells displayed strong contractile activity. Data points depict mean ± s.e.m. and one-way ANOVA was performed for each group (for culture confluency: *F(4,27) = 8.298, p < 0.0002; **F(4,28) = 5.708, p < 0.002; ***F(4,25) = 31.22, p < 0.0001)