Changes in nitric oxide, superoxide, and blood circulation in muscles overtime after warm ischaemic reperfusion in rabbit rectus femoris muscle

We present the sequence of changes in nitric oxide (NO) and superoxide (O-2 (-)) over time in reperfusion injuries. We examined both the changes in NO and O-2(-) over time and the blood flow in an isolated ischaemia-reperfusio n muscle model in rabbits. The ischaemic group comprised 8 animals which ha d had vascular pedicles clamped on to their rectus femoris muscles for 4 ho urs. The control group (n = 6) had a sham operation. Blood samples from the femoral vein proximal to the clamping point were collected before the oper ation, before clamping, before reperfusion, immediately after reperfusion, and 5, 15, 30, 60, and 120 minutes after reperfusion. NO was measured by Gr iess' method, and O-2(-) by chemiluminescence. Blood flow was measured with a laser Doppler flowmeter. The amount of NO increased significantly immedi ately after reperfusion, and 15 and 30 minutes after reperfusion in the isc haemic group, compared with the control group (p < 0.05). O-2(-) increased significantly at 5, 15, 60, 90 and 120 minutes after reperfusion, compared with the control group (p < 0.05). The blood flow volume curve increased by 1.4 times about four minutes after reperfusion compared with previously. A fter this it gradually decreased. The adverse effects of O-2(-) became appa rent when NO was extinguished by O-2(-).