Expression and relocation of B23 in the process of rat liver cell hyperplasia and liver regeneration

To study the B23 expression and relocation in the process of liver regeneration at different time periods after partial hepatectomy (PH) on healthy rats, and to study the feasibility of using B23 as a proliferation marker. Eighteen rats underwent partial hepatectomy (PH). The regenerative liver tissues were obtained at day 1, 2, 3, 4,and 7 after PH. The expression of B23 in hepatocytes of the regenerative tissues was measured using monoclonal antibody against nucleophosmin/B23 by Western blot and immunohistochemistry. The expression of proliferate cell nuclear antigen (PCNA) in these cells were measured using monoclonal antibody against PCNA by both methods for comparison with that of B23. Expression of B23 in the steady state of liver cells before PH was hardly detected by both methods. The increased expression of B23 in the regenerative liver cells was quantitatively changed like a parabolic curve at day 1 to days 7 after PH, with the peak expression of B23 at day 3 after PH. This quantitative variation of