Objective: To study the practicability of using red blood cells (RBC) as the carrier of SOD or GSH.Px and to observe the effects of RBC-SOD and RBC-GSH.Px on cerebral ischemia-reperfusion (I-R).
Methods: The method of hypotonic dialysis was used in encapsulating SOD or GSH.Px into rabbit RBC. The circulation half-lives (T1/2) of RBC-SOD and RBC-GSH.Px were determined in rabbits by 51Cr radiolabel. Lipid peroxidation (LPO) and nitric oxide (NO) in plasma and TTC staining of cerebrum were examined.
Results: T1/2 was 13.4 +/- 1.5 days (n = 6) for RBC, 13.7 +/- 1.0 days (n = 5) for RBC-SOD, and 7.3 +/- 2.5 days (n = 5) for RBC-GSH.Px. The concentration of NO reduced gradually as reperfusion continuing in control group, but it was a state of significant increase in NO concentration during the 4.5 hours of reperfusion, in RBC-SOD group. The increase of NO was inhibited by the administration of RBC-GSH.Px or (RBC-SOD + RBC-GSH.Px). The increase of LPO during cerebral I-R was inhibited by RBC-SOD or (RBC-SOD + RBC-GSH.Px). Staining with TTC showed that the RBC-SOD, RBC-GSH.Px and (RBC-SOD + RBC-GSH.Px) could effectively protect cerebrum For I-R damage, especially the last one.
Conclusion: Using RBC as the carrier of SOD or GSH.Px is practicable. Intact RBC-SOD and RBC-GSH.Px could scavenge active oxygen produced during cerebral I-R.