How to Establish a Minimal Invasive and Stable Carotid Artery Stenosis Rabbit Model? A Simple and Effective Carotid Artery Balloon Strain Technique

Background: The objective of this study is to establish a minimally invasive technique to create a stable carotid artery stenosis rabbit model. This article summarizes the specific methods and key points of this technology. Methods: The experiment studied a rabbit that was anesthetized through the vein. After the femoral artery was exposed, a minimally invasive needle was used to puncture the femoral artery, then the sheath was placed into the artery. We primarily put a catheter in the ascending aorta for angiography and then used a PT2 guidewire for super-selection. The PT2 guidewire was retained, and a balloon was placed in the right common carotid artery (CCA) through a guidewire to inflate it three times. Six rabbits in the 2- (2W) and 4-week (4W) groups were examined at 14 and 28 days, respectively. The rabbits in the control group received angiography at the beginning and 28 days later but without balloon injury. After angiography assessment, specimens of right CCA were dissected. Pathological and immunohistochemical examinations were performed on the collected specimens, and iFlow analysis was performed as well. Results: All the 18 animals which survived were observed. The rabbits in the 2W and 4W groups showed stenosis of the right CCA. Digital subtraction angiography showed the diameter was lower than that in the control group (1.04 ± 0.1, 0.71 ± 0.12, and 1.83 ± 0.08 mm in 2W, 4W, and control group, P < 0.05). Pathology also suggested carotid stenosis and obvious intimal hyperplasia. The results of immunohistochemistry showed that α-smooth muscle actin was highly expressed in the 2W and 4W groups, and the integrated optical density (IOD) value was higher than that in the control group (14,807.11 ± 1,822.3, 22,245.96 ± 1,212.82, and 6,537.16 ± 1,186.62 in the 2W, 4W, and control group, P < 0.05). Meanwhile, a cluster of differentiation 31 (CD31) was low expressed in the 2W and 4W groups, and the IOD value was lower than that in the control group (519.14 ± 44.4, 1,029.64 ± 98.48, and 1,502.05 ± 88.79 in the 2W, 4W, and control group, P < 0.05), which suggested endothelial damage and partial repair. The analysis by iFlow showed that the time-to-peak after balloon strain in the 2W and 4W groups were longer than that in the control group. Conclusion: We established a minimally invasive, effective, and safe method to establish a carotid artery stenosis rabbit model. The highlights of this technology were the application of minimally invasive methods, reducing surgical bleeding, infection, and related complications. This technology avoided the influence of tissue around CCA in the traditional carotid artery balloon injury model, which might lead to more accurate treatment outcomes.