Figure 2

Histology of testes of Npr2^slw/slwmice. (A-N) Hematoxylin and eosin-stained sections of testes of control (left low) and Npr2^slw/slw mice (right low). For histological analysis, n = 5 mice at 0 dpp n = 5 mice at 7 dpp, n = 3 mice at 14 dpp, n = 4 mice at 21 dpp, and n = 1 mouse at 28 dpp, n = 1 mouse at 35 dpp and n = 1 mouse at adult (n = 3, as after weaning mice all combined). At least 10 sections were observed for each testis. Original magnification was x1000 (A, B, C, D, E, F, G, and H) and x200 (I, J, K, L, M, and N). Bar indicates 100 μm (I, J, K, L, M, and N). (O) Delay of spermatogenic onset in Npr2^slw/slw mice. Cumulative bar graph depicting the percent of the most advanced cell types in seminiferous tubules over a whole testis cross-section was compared between control and Npr2^slw/slw testes at 14 dpp. N = 3 different mice of cross sections were observed for examine progression of spermatogenesis. Total number of tubules observed are 779 and 519 for control and Npr2^slw/slw, respectively. The data shown are means (cumulative bar) and SDs (bars). (P and Q) Increased cell death in juvenile testes of Npr2^slw/slw mice. TUNEL assay of Npr2^slw/slw testes at 21 dpp (P). Original magnification x200. Bar indicates 100 μm. Comparison of apoptotic cells in the seminiferous tubules of control and Npr2^slw/slw testes at 21 dpp (Q). N = 4 different mice of cross sections were observed for counting apoptotic cells. Total number of tubules observed are 799 and 502 for control and Npr2^slw/slw, respectively. The data shown are the means (columns) and SEs (bars).