Abstract: Objective To Analyze and discuss the changes in number,morphology,and function in the preservation period of apheresis platelets.Methods Countand observe the morphologyof platelets while determinethe glucose,lactic acid concentration,platelet P-selectin （CD62p） and platelet aggregation function.Results During in vitro preservation,platelets count and PH value were significantly lower when it comes toDay 5.Platelet morphology score significantly declined since the third day.The glucose concentration gradually decreased and lactic acid concentration showed a trend of rising.Compared with Day1,platelet aggregation function gradually reduced （P<0.05） in Day 3 and Day 5.Conclusion During in vitro preservation period of apheresis platelets,the platelet morphology and function dynamically changed,but were stable in the first three days.

Key words: Apheresis platelets, Preservation, Platelet P-selectin, Aggregation