Mitsuhiro Yamamaura, Yuji Miyamoto, Masataka Mitsuno, Hiroe Tanaka, Masaaki Ryomoto, Shinya Fukui, Yoshiteru Yoshioka
Department of Cardiovascular Surgery, Hyogo College of Medicine, Nishinomiya, Japan.
OBJECTIVES: At VAM 2010 & 2011, we have reported that preoperative injection of the free-radical scavenger, edaravone (Radicut®, Mitsubishi Tanabe Pharma Co., Japan) prevented reperfusion injury. In this study, we evaluated whether edaravone can reduce reperfusion injury if injected at the start of reperfusion.
METHODS: Male Lewis rats (525±78 g, n=10) were subjected to reperfusion injury models by clamping the bilateral common femoral arteries for 5 hours followed by de-clamping. Rats were divided into two groups and intraperitoneally injected with edaravone (group edaravone; 9.0 mg/kg, n=5) or saline (control group; n=5) at the same time as removing the clamps. Five hours after de-clamping, the muscles of lower extremity were harvested. Tissues were stained with hematoxylin & eosin (HE), in order to count the viable muscle cells. They were also stained with periodic acid-Schiff (PAS), in order to assess the glycogen storage in muscle cells.
RESULTS: The density of viable muscle cells in the group edaravone was significantly greater than that of control group (593±60 cells/mm2 vs. 258±31 cells/mm2, p<0.01). The mean percentage of PAS-positive area in the edaravone group was also significantly higher than that in control group (30.1±6.9 % vs. 7.3±2.1%, p<0.001, Figure attached, original 200x).
CONCLUSIONS: Our results suggest that edaravone injected at the start of reperfusion can also reduce muscle injury following leg ischemia in rats, storing a high level of glycogen in viable muscle cells. Therefore, edaravone might be useful in clinical settings following leg ischemia.
AUTHOR DISCLOSURES: S. Fukui, Nothing to disclose; M. Mitsuno, Nothing to disclose; Y. Miyamoto, Nothing to disclose; M. Ryomoto, Nothing to disclose; H. Tanaka, Nothing to disclose; M. Yamamaura, Grant in Aid for Researchers Hyogo College of Medicine 2011, Research Grants; Y. Yoshioka, Nothing to disclose.
Posted April 2012