AIM: To observe the cytotoxicity of rat serum containing Radix Dipsaci at different concentration on proliferation of human osteoblast-like cells.METHODS: The experiment was performed at Umbilical Cord Blood Bank and Medical Research Center of the Second affiliated Hospital of Sun Yat-sen University of Medical Sciences, and the Radioimmunoassay Center of Sun Yat-set University of Medical Sciences from January to July 2001. ①Preparation of the rat serum containing drug: 18 SD male rats were selected and randomly divided into 3 groups with 6 rats in Radix Dipsaci group, blank control group with 8 rats and estrogen group with 4 rats. After being treated with Radix Dipsaci, saline and estrogen, respectively with gastric perfusion according to body mass for 3 days, blood was gained. After contrifugation, supernatant was obtained. ②Human osteoblast-like cells were isolated and cultured according to references. ③Observation on cytotoxicity of rat serum containing Radix Dipsaci: The osteoblasts were planted at 1.0×108 L-1 and cultured for 24 hours. Then they were culture in the medium without any serum for the second 24 hours. At last, they were disposed with the medium contains 100%,50%,25%,12.5%,6.25% and 3% concentration of Radix Dipsaci rat serum. The cytotoxicity of Radix Dipsaci rat serum was scored by direct cytometry and MTT methods. ④Quantitative analysis on proliferation of human osteoblast-like cells: The cells were disposed with different concentration of rat serum, and divided into 5%, 10% and 20% Radix Dipsaci group, 5%, 10% and 20% estrogen 1 group, 5%, 10% and 20% blank control group with 5%, 10% and 20% estrogen 2 group.
The proliferation of cells was tested with 3H-Tdr and MTT.RESULTS: ①Observational result of cytotoxicity of serum containing Radix Dipsaci: The direct cytometry indicated that the cells had a good proliferation when the medium with 12.5% and 25% concentration of Radix Dipsaci rat serum. MTT results showed that A value was the highest. ②Effect of Radix Dipsaci on proliferation of osteoblast: The result of 3H-Tdr indicated that the proliferation of human osteoblast-like cells in the 10% Radix Dipsaci group, 10% and 20% estrogen 1 group and estrogen 2 at every concentration of rat serum group was higher significantly than that in the blank control group, 5% estrogen 1 group and 5% Radix Dipsaci group (P < 0.01). The MTT showed that the proliferation of cells in the 10% and 20% Radix Dipsaci group, 10% and 20% estrogen 1 group and 10% and 20% estrogen 2 group was higher obviously than that in the blank control group, 5% estrogen 1 group and the 5% Radix Dipsaci group (P < 0.01=. CONCLUSION: High concentration of Radix Dipsaci has inhibitory effect on the proliferation of osteoblasts, while low concentration of Radix Dipsaci has no effect on the proliferation of cells, and middle concentration of Radix Dipsaci has the strongest effect on the proliferation of cells.