ObjectiveTo evaluate the dynamic changes of blood flow and blood pressure of acute hindlimb ischemia of rats by laser Doppler flowmetry (LDF) and laser Doppler perfusion imaging (LDPI). MethodsThe acute hindlimb ischemia model of rats was established by resection of rats femoral arteries of left hindlimb. The blood flow and blood pressure between operated and nonoperated hindlimbs were examined by LDF on 2, 7, 14, 28, and 49 d after operation. And the blood flow was evaluated by LDPI on 7 d after operation. ResultsAll rats survived after operation and no hindlimb necrosis occurred. The mean score was 2 on 14 d after operation and 1 on 49 d after operation. The ratio of blood flow between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 1.31±0.439 (P=0.021). The ratio of blood flow on 7 d (0.82±0.538) and 14 d (0.93±0.294) after operation was significantly lower than that on 2 d after operation (P=0.032 and P=0.019), although the difference between the two former was not significant (P=0.502). Furthermore, the ratio of blood flow on 28 d after operation reached the bottom (0.41±1.970), which was obviously lower than that on 2, 7, and 14 d after operation (P=0.004, P=0.007, and P=0.006). The blood flow of operated hindlimbs recovered approximately the value before operation (0.98±0.093), which was significantly lower than that on 2 d (P=0.010), higher than that on 28 d (P=0.005), but not different from that on 7 d and 14 d after operation (P=0.126 and P=0.382). The ratio of blood pressure between operated and nonoperated hindlimbs on 2 d after operation significantly increased from 1 to 0.47±0.375 (P=0.031). The ratio of blood pressure decreased on 7 d after operation (0.44±0.118), which was not different from that on 2 d after operation (P=0.203). Furthermore, the ratio of blood pressure on 14 d after operation reached the bottom (0.35±0.115), which was obviously lower than that on 2 d and 7 d after operation (P=0.001 and P=0.036). On 28 d after operation, the ratio of blood pressure increased (0.54±0.146), which was significantly higher than that on 14 d after operation (P=0.008), while not different from that on 2 d (P=0.493) and 7 d after operation (P=0.551). The ratio of blood pressure recovered approximately the value before operation (0.97±0.094), which was significantly higher than that on 2, 7, 14, and 28 d (P=0.013, P=0.021, P=0.002, and P=0.031). ConclusionAcute hindlimb ischemia model of rats can be established by resection of rats femoral arteries of left hindlimb and the most serious stage of hindlimb ischemia is on 14-28 d after operation. LDF and LDPI are of importance for monitoring the dynamic changes of rats hindlimb ischemia after operation.
ObjectiveTo evaluate the feasibility of monitoring of permanent middle cerebral artery occlusion (MCAO) model in C57BL/6 mice by Laser Doppler flowmetry. MethodsC57BL/6 mice were divided into 2 groups randomly:sham group and permanent MCAO group. Permanent MCAO model was established with the method of suture inserted into the internal carotid artery. Sufficiency of MCAO was monitored by Laser Doppler flowmetry during ischemia in mice. The neurological deficit score was assessed and the cerebral infarction size was measured by 2, 3, 5-triphenytetrazolium chloride (TTC) staining technique twenty-four hours after MCAO. ResultsIn the MCAO group, the local blood flow was decreased from the preoperative value of (186.78±62.50) PU to the postoperative value of (25.80±7.66) PU. Cerebral blood flow was reduced by 90.4% during MCAO. The neurological deficit score was 2.48±0.36. The cerebral infarction area accounted for 39.79% by TTC staining. However, the cerebral blood flow fluctuations were not reduced and the neurological deficit score was found normal in the sham group. Furthermore, there was no cerebral infarction lesion in the sham group. ConclusionMonitoring by Laser Doppler flowmetry is efficient for evaluating the success rate of MCAO.