Abstract: Objective To assess the impacts of different concentrations of Salidroside (Sal) on the morphology, metabolism and activation of platelets during in vitro preservation. Methods We used a blood component separator to collect apheresis platelets, and evenly distributed them into five separate bags. One bag served as the control group (Group A), while the remaining four bags received varying concentrations of Sal solution, resulting in final Sal concentrations of 5 μmol/L (Group B), 25 μmol/L (Group C), 40 μmol/L (Group D), and 50 μmol/L (Group E). These platelets were then stored at room temperature (22±2) ℃ with agitation. On the 1st, 3rd, 5th, 7th, 10th, and 14th days of storage, samples were taken for platelet parameter analysis, blood gas biochemistry, thromboelastography, flow cytometry, and Elisa kit measurement of sCD40L concentration. Results 1) The platelet count of each group had no significant change with the prolongation of storage time (P>0.05). The mean platelet volume (MPV) remained stable in the first 10 days of preservation, but significantly increased at 14 days (P<0.05). The platelet volume distribution width (PDW) value showed varying degrees of change with the extension of preservation time (P<0.05). No significant differences were observed in platelet count, MPV and PDW among groups during the same preservation time. 2) Seven days after storage of monopexic platelets, all groups exhibited a significant decrease of pH value (P<0.05), a continuous rise of LAC value (P<0.05), as well as a remarkable decrease of GLU value (P<0.05). 3) There was no significant difference in the thromboelastography maximum amplitude (TEG MA) of apheresis platelets between the groups within the first 10 days of storage. However, on the 14th day, the TEG MA value was significantly lower than that of earlier time points (P<0.05). 4) During the preservation period, the expression rate of CD62P in platelets increased continuously, peaking on the 10th day (P<0.05), followed by a decrease on the 14th day (P>0.05). On the 5th and 7th day of preservation, the expression rate of CD62P significantly differed between the control group (Group A) and the experimental groups (P<0.05). 5) In the early stage of preservation, the concentration of soluble CD40 ligand (sCD40L) in all groups gradually increased, reaching a peak on the 5th day, and then gradually decreased, reaching its lowest level on the 14th day. There were significant differences compared with the 3rd and 5th day (P<0.05). However, no significant difference was noted in the expression rate of sCD40L among all groups during the same preservation time (P>0.05). Conclusion The addition of Sal to platelets does not compromise their normal function but can significantly inhibit platelet activation, which may help reduce platelet storage damage.

Key words: Salidroside, Platelet, Save, Activation