Figure 7. Collagen significantly increases in the whole ovary and around CLs in reproductively old mice. (A) Representative images depicting (I) PSR staining in a reproductively young ovary and (II) the same image in ImageJ software. (III) Representative image of an H&E-stained CL, (IV) the same CL with PSR staining, and (V) the CL in ImageJ. Scale bars are (I-II) 100 μm and (III-V) 25 μm. (B) Representative images of a reproductively old ovary and CL with the same histological techniques in (A). Scale bars are (I-II) 100 μm and (III-V) 25 μm. (C) Graph showing the percent of reproductively young and old ovaries positive for PSR (N = 10 ovaries per age group). A t-test was performed; asterisk denotes P = 0.019. (D) Graph showing analysis of the percent of PSR positive area in and surrounding CLs for both age cohorts. Each data point corresponds to one CL. A t-test was performed; asterisks denote P < 0.0001. Data are represented as mean ± SEM (C and D).