Fig. 6

Localization of H19 RNA in HF myocardium. Sections were derived from FFPE LV biopsies of HF patients and H19 RNA was detected by in situ hybridization in blue, using bright field microscopy (a, c). Vascular structures were identified in serial sections by staining for CD31, an endothelial marker (d). Colored arrows indicate matching H19/CD31 signals. For negative control, in situ hybridization was also carried out with a probe for an exogenous RNA, DapB of B. subtilis (f, h). Nuclei were detected by HOECHST 3332 counterstaining using fluorescence microscopy (b, e, g). The merge of H19 and HOECHST 3332 signals (c) shows both nuclear and cytoplasmic distribution of H19. Representative pictures are shown (n = 16; calibration bar = 20 µm; magnification 40×)