Fig. 4.

Normal morphology of the lung and heart of 16- to 19-month-old ERβ_ST^L−/L− mice. (a and b) Normal cellular composition of the lung of ERβ_ST^L−/L− females (hematoxylin and eosin). (c and d) Normal cardiomyocyte size and intercellular spaces in the heart of ERβ_ST^L−/L− males (modified Mallory's trichrome). (e and f) Normal pattern of f-actin distribution in the sarcomeres of ERβ_ST^L−/L−hearts; sections are stained with FITC-conjugated phalloidin. (g and h) Normal structure of intercalated discs in ERβ_ST^L−/L− hearts; transmission electron microscopy. (i) Normal mean alveolar surface in ERβ_ST^L−/L− female lungs (arbitrary units; pixels × 10³; means ± SEM). (j) Normal mean left ventricular wall surface in ERβ_ST^L−/L− male heart (arbitrary units; pixel × 10⁵; means ± SEM). A, alveolar lumen; CM, cardiomyocytes; E, endothelial cell; I and Z, I and Z bands, respectively; ID, intercalated disk; IS, intercellular spaces; M, mitochondria; P1 and P2, type 1 and 2 pneumocytes, respectively. Nineteen-month-old females of each genotype were used, 10 for histological analysis and 5 for alveolar surface measurement; 16-month-old males of each genotype were used, 8 for evaluation of cardiomyocytes size and left ventricle wall surface, 5 for f-actin staining and 3 for electron microscopy. (Scale bar: a and b, 40 μm; c–f, 100 μm; g and h, 2 μm.)