Proliferation studies

Ki67-positive cells and total cell numbers were counted throughout eight sections, with each section separated by 20 mm (to ensure counts were not duplicated) per heart. For NfatC1^Cre(+);Ift88^+/+ (control), a total of five individual anterior and posterior leaflets were analyzed. For NfatC1^Cre(+);Ift88^f/+ (conditional heterozygote), a total of eight individual anterior and posterior leaflets were analyzed. For NfatC1^Cre(+);Ift88^f/f (conditional knockout), a total of seven individual anterior and posterior leaflets were analyzed. The average number of Ki67-positive cells and total number of cells counted throughout the eight sections were averaged among the five leaflets analyzed per genotype. Measurements were compared to control data to obtain fold change values. To detect statistically significant differences between test groups with two-sided α = 0.05, Student’s t test was used. Error bars represent SD.