Fig. 1

Preparation and histology of zebrafish ventricular myocardial tissue slices.

(A) Excised zebrafish heart. Slices were sectioned along the short axis as displayed by the sectional plane. (B) Picture of a myocardial tissue slice. Dashed circle encloses the ventricular cavity used for mounting on the force setup. (C) Technique used for mounting of tissue slices. The slice is impaled on a glass capillary with a conic tip. The lumen of the capillary is placed on the tips of the J-shaped hooks and the tissue slice is pushed down. Afterwards the hooks with the slice are lowered into the medium-containing measuring chamber. (D-M) Histological and immunohistochemical stainings of myocardial tissue slices. HE staining of cryosections (8 µm) obtained from a myocardial tissue slice at day 0 (D), day 1 (G) and day 2 (K). Cyrosections stained against sarcomeric-α-actinin (green) at day 0 (E-F), day 1 (H-I) and day 2 (L-M). Nuclei are counterstained with Hoechst (blue).