Fig. 4.
Effect of NPY on cell division and proliferation of rat adult cardiomyocytes. Adult cardiomyocytes in culture were photographed without treatment after attachment on day 1 (A). These cells were then treated with NPY (10−8 M) and pretreated with BrdU for 5 days. Several adult myocytes photographed in phase contrast were seen dividing after NPY treatment at days 9 and 10 (B and B1). Cells stained for aurora B kinase for cytokinesis (C), phosphorylated histone H3 (H3P) for mitosis (D), and BrdU for DNA synthesis (E) were observed. Color codes are given at top in C–E. Quantitative and count data for DNA synthesis (DNA S), mitosis, and cytokinesis (Cytok) are shown in F. Additive effect of NPY and FGF on DNA synthesis is shown in G. Data are means ± SE of 20 independent experiments; *P <0.05.