Changes of reproductive activity of bone marrow mesenchymal stem cells in experimental chronic pancreatitis rats

Objective:To analyze the percentage and proliferation capacity of MSCs at different time points after CP induction.Methods:Experimental CP was induced in rats by intraperitoneal injection of L-arginine.Animals were sacrificed at 3 d,7 d and 14 d after model induction.Bone marrow cells were implanted for primary culture.Colony formation rate of bone marrow cells was calculated by CFU-F method.Surface markers CD29,CD44,CD45 on primary culture bone marrow cells were detected by flow cytometry,and percentages of CD29+,CD44+CD45-cells(MSCs) in different groups were calculated.Results:Colony formation rates in 3 d,7 d and 14 d groups were 19.33±3.56,24.67± 4.89 and 18.33 ±2.73,respectively,significantly higher than that of control(4.83 ±1.72,P 0.01).Percentages of CD29+,CD44+,CD45-Cells(MSCs) were(7.27±0.82)%,(7.94±2.11)% and(5.26±0.66)%,respectively,significantly higher than that of control group(3.37±0.55)%(P0.05).Conclusions:The percentage and proliferation capacity of bone marrow MSCs changes during the course of CP,with a first increasing then reducing process.