ABSTRACT
Objective To explore the reparation role of recombinant human bone morphogenetic protein-4 mature peptide (rhBMP-4m) on hematopoietic system injury induced by irradiation in mice.Methods Ninety BALB/c mice were randomly divided into normal control group,model group and rhBMP-4m treatment group,with 30 mice in each group.The mice in model group and rhBMP-4m treatment group were irradiated by 60Co γ-ray(7.5 Gy) for 200 s;while the mice in normal control group did not receive irradiation.After irradiation,the mice in model group were given physiological saline 1.0 mL by peritoneal injection per day for 6 days;the mice in rhBMP-4m treatment group were given rhBMP-4m 0.5 mg by peritoneal injection per day for 6 days.The peripheral white blood cell count and marrow mononuclear cells,the percent of CD34 + cells in marrow mononuclear cells of mice were detected on the first,third,fifth,seventh,ninth day after irradiation;the number of spleen nodus and the pleen weight/body weight ratio were detected at the ninth day after irradiation.Results There was no statistic difference in the number of peripheral white blood cells of mice among the three groups on the first day after irradiation(P ＞ 0.05).The peripheral white blood cell count of mice in model group was significantly lower than that in the normal control group on the third,fifth,seventh,ninth day after irradiation (P ＜ 0.01).There was no statistic difference in the number of peripheral white blood cells of mice between rhBMP-4m treatment group and model group on the third,fifth day after irradiation (P ＞ 0.05);the peripheral white blood cell count of mice in rhBMP-4m treatment group was significantly higher than that in model group on the seventh,ninth day after irradiation (P ＜ 0.05).The number of marrow mononuclear cells of mice in model group was significantly lower than that in the normal control group at each time piont after irradiation(P ＜ 0.05).There was no statistic difference in the number of marrow mononuclear cells of mice between the rhBMP-4m treatment group and model group on the first,third day after irradiation (P ＞ 0.05);the number of marrow mononuclear cells of mice in rhBMP-4m treatment group was significantly higher than that in the model group on the fifth,seventh,ninth day after irradiation(P ＜ 0.05).The proportion of CD34 + cells in mononuclear cells of mice in model group was significantly lower than that in the normal control group at each time piont after irradiation(P ＜0.01).There was no statistic difference in the proportion of CD34 + cells in mononuclear cells of mice between the rhBMP-4m treatment group and model group on the first,third day after irradiation (P ＞ 0.05);the proportion of CD34 + cells in mononuclear cells of mice in rhBMP-4m treatment group was significantly higher than that in the model group on the fifth,seventh,ninth day after irradiation(P ＜ 0.05).Compared with the normal control group,the number of spleen nodus was increased and the spleen weight/body weight ratio of mice was decreased in model group on the ninth day after irradiation(P ＜ 0.05);the number of spleen nodus and the spleen weight/body weight ratio of mice in rhBMP-4m treatment group were significantly higher than those in the model group on the ninth day after irradiation (P ＜ 0.01).Conclusion rhBMP-4m can accelerate the reconstruction of bone marrow hematopoietic system of mice with hematopoietic system injury induced by irradiation.