 Introduction Storage of red cells is associated with some significant biochemical and metabolic changes. Red cells when exposed to oxidative stress during storage as it was reflected by increasing levels of lipid peroxidation, Hb oxidation and osmotic lysis. These deleterious changes were more pronounced after gamma irradiation at 25 Gy. L carnitine, a naturally occurring antioxidant, known for its role in facilitating mitochondrial beta oxidation of long chain fatty acids and membrane repair.  Materials and Methods A total of 30 red cell units were studied. The blood bags were divided in two aliquots. L carnitine was added to one aliquot and other half without L carnitine served as a control. Both the halves were irradiated at 25 Gy and stored for 28 days. Markers of oxidative injury and membrane damage were investigated to assess role of L carnitine as antioxidant.  Results The mean levels of plasma K+ and supernatant Hb and MDA were significantly lower in L carnitine fortified irradiated red cells compared to gamma irradiated red blood cells without carnitine. (mean plasma Hb 0.363 gm/dl vs 0.281 gm/dl, mean K+ 51.24.4 mmol/L v/s 46.33.3* mmol/L and mean MDA 5.010.99 mmol/L v/s 4.04*1.13 mmol/L). L carnitine provided beneficial effect against such radiation induced red cell damage.  Conclusion Lower levels of markers of red cell membrane damage and oxidative injury were observed in L carnitine fortified irradiated red blood cells compared to non-irradiated. Since L carnitine is also a naturally occurring compound, it can be added to the blood bags for protection of red blood cells against oxidative damage.

Keywords : Oxidative Injury, Gamma Irradiation, L Carnitine, Red Cell Storage Lesion.