Figure 3: Double Immunostaining of Mid-Heart Sections Showing M1-Activated and M2-Positive Macrophages

Double immunostaining of mid-heart sections show a greater predominance of M1-activated macrophages over time with little change in percentage of M2-positive macrophages. Total macrophages were detected by anti-CD68 and liquid permanent red staining (red), whereas macrophage activation markers were identified by the relevant antibodies and DAB staining (brown). Macrophage-rich areas were analyzed as outlined in Methods. Examples of double-stained macrophages are highlighted by arrows in A. Original magnification ×400. Changes in percentages of double-stained macrophages over time for inducible nitric oxide synthase (iNOS) (B), major histocompatibility complex (MHC) class II (C), and CD163 (D). The number of animals per group were as follows; control n = 6, day 1 to 14 n = 5 for each time point. Statistical difference in the percentage iNOS, MHC class II, and CD163-positive macrophages between control rats and those injected with isoprenaline were calculated with p values denoted above each bar. Values in bold indicate statistically significant differences compared with the control group.