Figure 7

Muscularis thickness and collagen organization. Representative 40 × histological images of Masson’s Trichrome (a) and Picrosirius Red (b) stains along the circumferential (i, iii, v, vii) and axial (ii, iv, vi, vii) planes in the Fbln5^+/+ (i, ii), Fbln5^+/− (iii, iv), Fbln5^-/- with grade 1 POP (v, vi), and Fbln5^-/- with grade 2/3 POP (vii, viii) mice. The muscular layer is outlined with a black dashed line. Vaginal muscularis thickness is reported along the circumferential (c) and axial (d) planes for the Fbln5^+/+ (black; n = 3), Fbln5^+/− (grey; n = 3), Fbln5^-/- with grade 1 POP (light grey; n = 3), and Fbln5^-/- with grade 2/3 POP (dark grey; n = 3) mice. Collagen alignment ratio is reported along the circumferential plane (e). Fibulin-5 insufficiency and POP significantly affected collagen fiber alignment ratio along the circumferential plane (p < 0.001). The alignment ratio decreased in the Fbln5^−/− vagina with grade 1 (p = 0.006) and 2/3 (p = 0.01) POP compared to the Fbln5^+/+. The alignment ratio decreased in the Fbln5^−/− vagina with grade 1 (p = 0.002) and 2/3 (p = 0.004) POP compared to the Fbln5^+/−. Collagen alignment ratio is reported along the axial plane (f). Fibulin-5 insufficiency and POP significantly affected collagen fiber alignment ratio along the axial plane (p = 0.002). The alignment ratio decreased in the Fbln5^−/− vagina with grade 1 (p = 0.008) and 2/3 (p = 0.02) POP compared to the Fbln5^+/+. The alignment ratio decreased in the Fbln5^−/− vagina with grade 1 (p = 0.005) and 2/3 (p = 0.01) POP compared to the Fbln5^+/−. Layers of the vagina are denoted as: epithelium (e), subepithelium (s), muscularis (m), and adventitia (a). Data is reported as mean ± SEM. Statistical significance is denoted by *p < 0.05 and **p < 0.01.