Different biomechanical properties of medial and adventitial layers of thoracic aorta in Wistar-Kyoto and spontaneously hypertensive rats  

作　　者：Wei-qing HAN Jing CHEN Ling-yun WU Ding-liang ZHU Ping-jin GAO 

机构地区：[1]State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Vascular Biology and Department of Hypertension, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China [2]Laboratory of Vascular Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200025, China [3]Shanghai Institute of Hypertension, Shanghai 200025, China

出　　处：《Acta Pharmacologica Sinica》2010年第10期1319-1323,共5页中国药理学报（英文版）

摘　　要：Aim： To evaluate the biomechanical properties of thoracic aorta with or without adventitia, and to determine whether there are corre- sponding changes with hypertension. Methods： Normotensive Wistar-Kyoto （WKY） rats and spontaneously hypertensive rats （SHR） at the age of 16 and 32 weeks were used Thoracic aortic adventitial layer was mechanically separated from thoracic aorta and the adventitia-denuded artery ring was viewed as thoracic media. A load-strain curve was obtained by stretching the ring-shaped intact thoracic aorta or thoracic media with a tensile testing machine. Then, the slope of the load-stain curve at 30%-40% strains was viewed as the elastic stiffness at physiological load, whereas the slope near the breaking point was calculated as maximum stiffness. The maximum load is the load at the breaking point. Results： There was no significant difference in elastic stiffness and maximum stiffness of intact thoracic aorta between SHR and age- matched WKY. The elastic stiffness of intact thoracic aorta showed no significant difference from that of thoracic media in WKY and SHR at both ages. In contrast, both maximum stiffness and maximum load were reduced in thoracic media compared with intact tho- racic aorta in SHR and WKY at both ages. Conclusion： These results indicated that vascular adventitia contributes to maximum stiffness, but not elastic stiffness in both SHR and WKY.Aim： To evaluate the biomechanical properties of thoracic aorta with or without adventitia, and to determine whether there are corre- sponding changes with hypertension. Methods： Normotensive Wistar-Kyoto （WKY） rats and spontaneously hypertensive rats （SHR） at the age of 16 and 32 weeks were used Thoracic aortic adventitial layer was mechanically separated from thoracic aorta and the adventitia-denuded artery ring was viewed as thoracic media. A load-strain curve was obtained by stretching the ring-shaped intact thoracic aorta or thoracic media with a tensile testing machine. Then, the slope of the load-stain curve at 30%-40% strains was viewed as the elastic stiffness at physiological load, whereas the slope near the breaking point was calculated as maximum stiffness. The maximum load is the load at the breaking point. Results： There was no significant difference in elastic stiffness and maximum stiffness of intact thoracic aorta between SHR and age- matched WKY. The elastic stiffness of intact thoracic aorta showed no significant difference from that of thoracic media in WKY and SHR at both ages. In contrast, both maximum stiffness and maximum load were reduced in thoracic media compared with intact tho- racic aorta in SHR and WKY at both ages. Conclusion： These results indicated that vascular adventitia contributes to maximum stiffness, but not elastic stiffness in both SHR and WKY.

关 键 词：thoracic aorta media ADVENTITIA elastic stiffness maximum stiffness spontaneously hypertensive rats 

分 类 号：Q463[生物学—生理学] Q5