Protective effects of glycine on flap after ischemia reperfusion injury: an experimental study in rats

Objective To research the effects and mechanisms of glycine with different concentration on flaps after ischemia reperfusion injury. Methods Fifty three-month old healthy male SD rats were randomly divided into 5 groups. The abdominal island flaps were made. And 30 minutes before blocking blood flow, 1.5 ml 0.9% saline (group A), 50 mmol/L glycine (group B), 100 mmol/L glycine (group C), 400 mmol/L glycine (group D) and 1000 mmol/L glycine (group E) were injected into the pedicle artery of the flaps respectively. After 6 hours of ischemia, 1.5 ml 0.9% saline or glycine with different concentration was injected intraperitoneally 5 minutes before reperfusion. Blood samples were collected from pedicle veins at 1, 6 and 12 hours after reperfusion to determine the plasma concentration of tumor necrosis factor α (TNF-α). The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) were measured at 12 hours after reperfusion. Results The levels of TNF-alpha and MDA in different concentrations of glycine group were significantly lower than those in saline group, while the levels of SOD were significantly higher than those in saline group (P<0.05). The difference between D, E group with higher glycine concentration and B, C group with lower glycine concentration had statistical significance (P<0.05). Conclusion Glycine can alleviate the ischemia reperfusion injury of rat flaps by decreasing TNF-α and MDA levels in plasma and increasing SOD levels. Key words: Glycine; Reperfusion injury; Flaps; TNF-α