Fig. 8. Spermatogonial proliferation and differentiation are independently affected by RyR inhibition. Testicular fragments were cultured for 24, 48 and 72 hours in the presence of 20 ng/ml FSH, with or without 300 µM ryanodine. (A) Percentages of tubules displaying BrdU-labelled spermatogonia. (B) Percentages of tubules displaying meiotic cells. Labelling and counting were performed as described in Materials and Methods. Each value represents the mean ± s.e.m. of at least 200 tubules for each experimental condition, obtained in two independent experiments. (A) FSH+Ry versus FSH at 72 hours: P<0.001; (B) FSH+Ry versus FSH at 48 and 72 hours: P<0.001.