Fig. 7. Effects of blocking RyR channels on spermatogonia proliferation and differentiation. Testicular fragments were cultured for 3 days with 100 µM or 300 µM ryanodine (Ry) or 20 ng/ml FSH (Ry) alone, and combinations of 20 ng/ml FSH with 100 µM Ry, 300 µM ryanodine or 300 µM 8-Br-cADPR, and eventually labelled with BrdU for 5 hours. (A) Percentages of tubules with BrdU-labelled spermatogonia; (B) percentages of tubules containing meiotic cells. Cell counting was performed as described in Materials and Methods. Values are the mean ± s.e.m. of three independent experiments. FSH+Ry 300 µM versus FSH: P<0.001; FSH+300 µM 8-Br-cADPR versus FSH: P<0.001.