Reduced vasoconstrictor response after angioplasty in normal rabbit aortas.

Angioplasty was performed on rabbit aortas in vivo. During balloon catheter inflations, the aortic diameters increased by 29%-75%; after deflation, there was persistent dilation of the treated segments by 11%-45%. Aortic strips removed from dilated and nondilated segments were tested for vasoconstrictor response in vitro. The vasoconstrictor response was attenuated in proportion to the effective stretch applied to the aorta in vivo. It was concluded that angioplasty can induce paralysis of smooth muscle.