Figure 5.

ECM KD Leads to Preserved Cardiac Mechanics with Age. (A) To the left, motion-mode images of a heart sequentially loaded by increasing relative viscosity, υ, by increasing Ficoll w/v% in the hemolymph in which the fly hearts are bathed. Arrows indicate where systole and diastole are located in the motion-mode images. To the right, m-mode image expanded to show contraction length (CL) in blue, shortening interval (SI) in green, and lengthening interval (LI) in red used for velocity measurements below. (B) Heart wall shortening (contraction) and lengthening (relaxation) velocities were assessed under viscous load and fit by Hill’s model for each genotype and age. (C) Fractional shortening were measured under viscous load for each indicated genotype and age. Data represented as mean ±s.e.m. n>20. All viscous load data were analyzed with 2-way-ANOVA with post hoc Bonferroni test. Significance indicates load/genotype as source of variance. *p<0.05, **p<0.01, ***p<0.001 (D) Survival curves for indicated genotypes show median survival indicated by the dashed black line for each genotype. ***p<0.0001