Objective: To study the proliferation of artery after hydraulic dilation under different pressures.
Material and methods: Right carotid arteries of New Zealand white rabbits (group A, B, C, D) were dilated by hydraulic dilation under different pressures (0, 40, 80, 120 Kpa). The arterial caliber, thickness of tunica intima (TI) and smooth muscle (SM) were measured with TJTY-300 automatic medical photograph analyzer at 0, 1, 2 weeks, respectively after dilation.
Results: 1) The arterial caliber of group B was greater than that in group A (P < 0.05, P < 0.01) at 0 and 1 week after hydraulic dilation, but no difference was found in 2 weeks after dilation. The thickness of TI and SM of group B was not different from group A at every time point. 2) The arterial calibers of group C, D were significantly larger than that of group A immediately and at 1 week (P < 0.01, P < 0.01). Group B, D showed no difference with group A (P > 0.05) at 2 weeks. The thickness of TI and SM of group C, D had no difference with group A (P > 0.05) immediately, but greater than group A at 1 and 2 weeks (P < 0.01, P < 0.01).
Conclusion: 1) Arterial caliber can be increased by hydraulic dilation under different pressures. But hydraulic dilation over 80 Kpa pressure may lead to proliferation of TI and SM. 2) It is safe for arterial hydraulic dilation to be conducted under pressure of 40 Kpa.