Single low shear stress results in atherosclerosis in vivo

摘要

Objective: Whether single low shear stress can result in atherosclerosis without hyperliposis-diet in vivo or not is unknown. Methods: Based on an electromagnetic blood flow meter and a method to determine the pulsatile shear stress from blood flow rate waveform and its software, we developed an in vivo pulsatile blood flow rate-shear stress determining system. The left external carotid arteries of 20 adult New Zealand white rabbits were ligated and the rabbits were fed with a standard chow for 2, 4, 8 or 12 weeks,then the common carotid arteries of 2 sides in each rabbit were harvested for morphologic test. Results; The ligation reduced pulsatile shear stress of left common carotid significantly, for example, τ_(mean) changed from(21. 16? 7. 17) dynes/cm~2 to(3. 13 ± 2. 28) dynes/cm~2(p = 2. 176E-21) .meanwhile ,the pulsatile shear stress of right common carotid did not change significantly,which lasted more than 12 weeks. Atherosclerotic plaques were found after 8 and 12 weeks in pulsatile-low-shear-stress left (not normal-shear-stress right) common carotid arteries. Conclusion: Single pulsatile low shear stress can result in atherosclerosis.lt supports the pulsatile low shear stress (not hypolipidemia) is the key risk factor for atherosclerosis.