Functions of Glycosylation Cooled Rabbit Platelets In Vivo and In Vitro.

This study was aimed to investigate functions of glycosylation cooled rabbit platelets in vivo and in vitro and the method to store cold platelets with UDP-gal. We collected rabbit heart blood, prepared concentrated platelet suspensions in a normal way to which we added UDP-Gal, and then stored them for ten days in 4° refrigerator. Thereafter platelet counts, mean platelet volume, platelet distributing width, platelet aggregation function, the activity to urge coagulation including PF3aT and APCT and apoptosis were determine- d. Meanwhile, survival time in vivo was tested after cold-stored rabbit platelets labeled with Cr⁵¹ were transfused into rabbits. Rabbit ear bleeding time and percentage plate recovery(PPR) were determined 1 hour and 24 hour after they were transfused into rabbit thrombocytopenia model. Results show that there was not significant difference in PLT counts, MPV, PDW, PF3aT and APCT between UDP-Gal cold-stored platelet group and fresh platelet group(p>0.05). On the contrary, platelet counts decreased significantly, MPV, PDW jumped and PF3aT and APCT went down in cold control group compared to fresh platelet group(p<0.01). Apoptosis increase in UDP-Gal cold-stored platelet group compared with fresh platelet group(p<0.05), but was significantly lower than that in cold control group(p<0.01). Although PagT(inducing reagent: C-PG) decreased, it could still be above 50% of fresh platelets. Survival time in rabbit vivo was close between UDP-Gal cold-stored platelet group and fresh platelet group(p<0.05). Survival rate seventy-two hours after transfusion in fresh platelet group, UDP-Gal cold-stored platelet group and cold control group was 57.5%±7.2%,50.3%±6.3% and 0.1%±0.1% respectively. Rabbit ear bleeding time was significantly shortened after transfusion of galactosylation cooled rabbit platelet (p<0.01), In contrast, it had less change in cold control group(p>0.05). PPR was 66.1%±0.5%,47.8%±0.6%;60.9%±0.3%,41.6%±0.4%;47.7%±0.5%,9.4%±0.5% respectively in fresh platelet group, UDP-Gal cold-stored platelet group and cold control group. PPR after transfusion of galactosylation cooled rabbit platelet had no statistical difference compared with that of fresh platelet group(p>0.05), and they in both groups were much higher than that in cold control group(p<0.01).

Conclusion: Galactosylation can improve functions of cooled rabbit platelets in vivo and in vitro. and prolong the storage time of them.