Evaluation of Coronary Endothelial Function by Catheter-Type NO Sensor in High-Fat-Diet-Induced Obese Dogs

• Published in: Circulation Journal 2009, Vol.73(3), pp.562-567
• Main Authors: Kume, Teruyoshi, Kawamoto, Takahiro, Okura, Hiroyuki, Neishi, Yoji, Hashimoto, Ken, Hayashida, Akihiro, Watanabe, Nozomi, Kanda, Yukiko, Mochizuki, Seiichi, Goto, Masami, Yoshida, Kiyoshi
• Format: Article
• Language: English
• Subjects: Acetylcholine - pharmacology; Animals; Blood Glucose - metabolism; Cardiac Catheterization - instrumentation; Cardiac Catheterization - methods; Catheters; Coronary circulation; Coronary Circulation - drug effects; Coronary Circulation - physiology; Coronary Vessels - physiology; Dietary Fats - pharmacology; Dogs; Endothelium, Vascular - metabolism; Female; Insulin - metabolism; Male; Metabolic syndrome; Nitric oxide; Nitric Oxide - blood; Obesity; Obesity - metabolism; Obesity - physiopathology; Vasodilator Agents - pharmacology
• ISSN: 1346-9843; 1347-4820
• DOI: 10.1253/circj.CJ-08-0789

Background: Direct measurement of plasma nitric oxide (NO) concentration is possible with a newly developed catheter-type sensor. Methods and Results: Adult mongrel dogs (n=5) were fed a high-fat diet (120 kcal · kg-1 · day-1) for 8 months, then endothelial function was assessed by the change in NO concentration induced by acetylcholine (ACh) (ΔNO). Simultaneously, average peak velocity (APV) was obtained by Doppler guide wire. Although fasting plasma glucose levels did not change after high-fat diet, fasting plasma insulin levels increased significantly (103±36 vs 106±27 mg/dl, P=0.89 and 0.15±0.15 vs 0.26±0.07 ng/ml, P=0.04, respectively). ACh-induced peak APV after high-fat feeding was not significantly different from that at baseline (ACh 0.1 μg/kg; 43±17 vs 51±7 cm/s, P=NS, ACh 0.4 μg/kg; 45±20 vs 47±16 cm/s, P=NS, respectively). The ΔNO was significantly smaller after high-fat diet than at baseline (ACh 0.1 μg/kg; 2.6±1.6 vs 1.0±0.5 nmol/L, P=0.03, ACh 0.4 μg/kg; 3.8±2.3 vs 1.8±1.1 nmol/L, P=0.04, respectively). Conclusions: In high-fat-diet-induced obese dogs NO production was impaired in the early stage when the coronary flow response to ACh may be preserved. (Circ J 2009; 73: 562 - 567)