Abstract: Objective To preliminarily explore the effects of different concentrations of polyamine nitric oxide donor Spermine Tetrahydrochloride on platelet activation at different time points during platelet storage and to discuss its relevant mechanism. Methods The apheresis platelets stored for 1 d,3 d,and 5 d were divided into experimental groups （groups A,B,C,D,and E） and control groups（group F）. 40 μL of 10 mmol/L,20 mmol/L,30 mmol/L,40 mmol/L,and 50 mmol/L Spermine Tetrahydrochloride were added to the experimental groups. And an equal amount of PBS solution were added to the control group. Fluorescence enzyme labeling method was used to detect the nitric oxide content of platelets,and flow cytometry was used to detect the expression of CD62p on the platelet membrane surface. Results After adding Spermine Tetrahydrochloride to apheresis platelets at different storage time points,the nitric oxide content of apheresis platelets increased,and the expression of CD62p decreased,which was statistically significant（P<0.05）; The higher concentration of Spermine Tetrahydrochloride were added,the higher nitric oxide concentration and the lower the CD62p expression in the platelets,and when the concentration of Spermine Tetrahydrochloride reach to 40 mmol/L it tends to be stable. Conclusion Spermine Tetrahydrochloride,a polyamine nitric oxide donor,can provide nitric oxide to platelets and inhibit platelet activation to a certain extent,which is related to the concentration of Spermine Tetrahydrochloride .

Key words: Platelet activation, Platelet storage, Nitric oxide donor, CD62p