Skin Tissue Changes Following Thermal Injury in the Paralysed Lower Limb of Spinal Injured Rats

OBJECTIVE: To prove that the skin of paralysed limb of spinal injured rat is more susceptible to a thermal injury than control, and to find out that the possible relating factors for explaining the increased susceptibility of skin. METHOD: Of total 69 male Sprague-Dawley rats, 50 were randomly divided into two groups, the spinal injured of which cords were transected at T10-13 level and the control. They were subdivided into 5 subgroups according to the duration of thermal injury. Infrared ray was used for thermal injury. Arterial cannulation was done in the femoral artery for blood gas analysis. Temperature was measured with a digital thermometer. Biopsy samples were stained with HE, and also immunohistochemical staining for heat shock protein 70 (HSP-70) was done. RESULTS: After thermal injury, the spinal injured group showed more severe tissue damage and a higher temperature elevation than the control. There was a tendency of decreased blood pH and pO2, and increased pCO2. Contrary to the control, the immunoreactivity of HSP-70 was very tiny or rarely present in the spinal injured group. CONCLUSION: This study suggest that the increased susceptibility of skin to the thermal injury in spinal injured rats may be related to the vasomotor instability. And, the poor expression of HSP-70 from the skin of spinal injured rat can be a factor for the explanation of the defective cellular protective response in spinal cord injury.

Heterotopic Heart Transplantation in the Rat Model / 대한흉부외과학회지

In 1964, Abbott and Colleagues published the world's first heterotopic heart transplantation technique in the rat. Their method established circulation by end-to-end anastomoses of the graft's aorta and pulmonary artery to the recipient's abdominal aorta and Inferior Vena Cava (IVC), respectively. In 1966, Tomita et al altered Abbott's technique by employing end-to-side rather than end-to-end anastomoses, thus eliminating the hind leg paralysis that sometimes resulted from Abbott's technique. In order to prevent postsuture hemorrhage (since 7-0 silk suture was the finest available at that time), Tomita's aortic anastomosis was done with double up-and-down continuous suture technique. A single layer continuous anstomosis effected the pulmonary artery-IVC anastomosis. The availability of Nylon monofilament suture made it possible for Ono and Lindsey to use a single layer suture technique for the aortic end-to-side anastomosis in their modified rat heart transplantation. We observed survival time between control group and Immunosuppression (Cyclosporine administration, 10mg/Kgx4 times postoperatively) group after heterotopic heart transplantation in the rat model. The cyclosporine adminstration group survived longer than the control group, thus we concluded that cyclosporine was based on Immunosuppressive drugs.