Abstract： Objective To compare and analyze the effects of different activators on the release curve of TGF-β1 and PDGF-AB in platelet rich plasma(PRP). Methods A total of 36 ml peripheral venous blood was obtained from 10 healthy adult volunteers, and the PRP was made by secondary centrifugation. The platelet activator was made by bovine thrombin 1000 U in 1 ml 10％ calcium chloride solution. The Thrombin-PRP group was made by PRP and the activator in a ratio of 10:1.The Calcium chloride-PRP group was made in a ratio of 10:1 by PRP and 10％calcium chloride solution instead. The fresh whole blood(whole blood group) and inactived PRP(PRP group) were used as the control groups. The 4 groups were incubated in warm water of 37℃for 0, 1, 8, 24, 72 and 168 h. A quantitative sandwich enzyme-linked immunosorbent assays(ELISA) was used to examine the amount of TGF-β1 and PDGF-AB in different time points of each group. The release curves of TGF-β1 and PDGF-AB were based on afore-mentioned data, and then comparisons of the release curves of TGF-β1 and PDGF-AB in different groups were performed by repeated measurement variance analysis. Results (1)The levels of TGF-β1 and PDGF-AB in the whole blood group and the PRP group continued to increase within 168 h. PRP immediately formed into a gel after mixture with thrombin combined and calcium chloride, and the concentrations of TGF-β1 and PDGF-AB reached the peak&nbsp;in 1 h after activation;increased from (42±21)ng/ml and (77±18)ng/ml to (84±21)ng/ml and (124±35)ng/ml, respectively, and then decreased gradually. The release curve was direct and rapid. The PRP became a gel state in approximate 1 h after mixture with calcium chloride, and the concentrations of TGF-β1 and PDGF-AB were slowly rising and remained high at 168 h. (2)The AUC0-168h of TGF-β1 and PDGF-AB in the PRP group was higher than that in the whole blood group(all P<0.05), and the AUC0-168h of TGF-β1 in the Calcium chloride-PRP group was higher than that in the Thrombin-PRP group(Z=-2.26,P<0.05).However, there was no significant difference in the AUC0-168h of PDGF-AB between the Calcium chloride-PRP group and the Thrombin-PRP group(Z=-1.512,P=0.131). Conclusion Using calcium chloride as activator can get a higher release concentration of TGF-β1 and PDGF-AB and a longer release time, with the largest area under the curve.