Changes of rabbit aorta lumen cross-sectional area due to various vasoactive drugs: Intravascular unltrasound observation

Ni Zhu-hua, Yang Xin-chun, Wang Le-feng, Xia Kun, Ge yong-gui, Wang Hong-shi, Li Wei-ming, Xu Li, Chi Yong-hui, Liu Yu

Heart Center, Beijing Chaoyang Hospital, Capital University of Medical Sciences, Beijing  100020, China

Ni Zhu-hua☆, Doctor, Attending physician, Heart Center, Beijing Chaoyang Hospital, Capital University of Medical Sciences, Beijing  100020, China nizhuhua@sina.com

Correspondence to: Yang Xin-chun, Chief physician, Professor, Doctor supervisor, Heart Center, Beijing Chaoyang Hospital, Capital University of Medical Sciences, Beijing  100020, China
yangxc@medmail. com.cn

Received: 2008-03-03

Abstract
BACKGROUND: Intravascular ultrasound can not only be used to determine whether lesion exists or not and identify the quality of lesion on vessel wall precisely, but also can be applied to observe vessel function with a direct pattern accurately.
OBJECTIVE: To approach whether intravascular ultrasound can be used to assess vascular changes due to drug intervention.
DESIGN, TIME AND SETTING: The observational trial was conducted in the Cardiac Catheter Labaratory of Beijing Chaoyang Hospital, Capital University of Medical Sciences between March 2006 and September 2006.
MATERIALS: Twenty-five New Zealand white rabbits, weighing 2.5-3.5 kg, after anaesthesia their femoral artery and common carotid artery were dissected and punctured and then put in a 5F sheath, respectively.
METHODS: The sheath deployed in the carotid artery was connected with the pressure tranducer and the blood pressure and electrocardiogram were monitored on the multichannel physiologic recorder. With the help of X-ray fluoroscopy, a 20 MHz ultrasound catheter was inserted into abdominal or thoracic artery through the sheath deployed in the femoral artery. After the condition became stable, various concentrations of acetylcholine, nitroglycerin and papaverine were injected into vessel through auricular edge vein at the dose of 2 mL/kg within 1 minute. The adenosine triphosphate was given bolus injection. The blood pressure, electrocardiogram and intravascular ultrasound image were recorded simultaneously during injection. Rabbits, if their blood pressure and heart rate could return to baseline level, would be administrated all above drugs with various concentrations, if the blood pressure and heart rate could not return to baseline level, further drug administration would be stopped, then the study ended. The blood pressure and heart rate must return to baseline level before each administration.
MAIN OUTCOME MEASURES: The blood pressure, electrocardiogram and intravascular ultrasound image were recorded simultaneously during injection. Ultrasound image was replayed and the vessel diameter and vessel area were measured.
RESULTS: It was found that if the luminal diameter and luminal area of big elastic artery decreased, the corresponding blood pressure dropped. Various concentrations of acetylcholine, nitroglycerin, papaverine and adenosine triphosphate could all render the luminal diameter and luminal area decreased and blood pressure dropped. Comparing with the basal condition, the differences were statistically significant (P < 0.05, P < 0.01).
CONCLUSION: Intravascular ultrasound can be used to observe vessel reactions to various drugs, especially vasoactive drugs, consequently intravascular ultrasound can also be used to screen vasoactive drugs.

Ni ZH, Yang XC, Wang LF, Xia K, Ge YG, Wang HS, Li WM, Xu Li, Chi YH, Liu Y. Changes of rabbit aorta lumen cross-sectional area due to various vasoactive drugs: Intravascular unltrasound observation.Zhongguo Zuzhi Gongcheng Yanjiu yu Linchuang Kangfu 2008;12(28):5427-5431(China) [www.zglckf.com/zglckf/ejournal/upfiles/08-28/28k-5427(ps).pdf]