Cell proliferation and apoptosis in mouse kidney during postnatal development

Objective:To observe the expression of proliferating cell nuclear antigen (PCNA) and the cell apopto- sis,so as to investigate the activity of cell proliferation and apoptosis in the mouse kidney during postnatal devel- opment.Methods:The expression of PCNA and apoptosis were examined in the mouse kidney 1-70 days after birth by immunohistoehemical technique and TdT-mediated dUTP nick end labelling (TUNEL).Results:The ac- tivity of cell proliferation was prominent after birth.At the early stage the PCNA-positive cells were abundant. Proliferative activity tended to decrease gradually as the renal developmental stage proceeded and eventually var- nished.At the same time,apoptotic cells were presented.The peak of cell death was later than the peak of cell proliferation.Conclusion:Cell proliferation and apoptosis exist widely in the mouse kidney during postnatal de velopment.The positive rate of PCNA is high 1-70 days after birth,and the peak of apoptosis is later than that of cell proliferation.Both of apoptosis and proliferation are weak 28-70 days after birth.