Adaptation of Vasomotor Function of Human Coronary Arterioles to the Simultaneous Presence of Obesity and Hypertension

• Published in: Arteriosclerosis, thrombosis, and vascular biology Vol. 27; no. 11; pp. 2348 - 2354
• Main Authors: Fulop, Tibor, Jebelovszki, Eva, Erdei, Nora, Szerafin, Tamas, Forster, Tamas, Edes, Istvan, Koller, Akos, Bagi, Zsolt
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA American Heart Association, Inc 01.11.2007; Hagerstown, MD Lippincott
• Subjects: Aged; Arterioles - physiopathology; Atherosclerosis (general aspects, experimental research); Biological and medical sciences; Blood and lymphatic vessels; Body Mass Index; Brachial Artery - diagnostic imaging; Brachial Artery - physiopathology; Bradykinin - pharmacology; Bradykinin - physiology; Cardiology. Vascular system; Cardiovascular system; Coronary heart disease; Coronary Vessels - physiopathology; Diseases of the peripheral vessels. Diseases of the vena cava. Miscellaneous; Female; Heart; Humans; Hypertension - complications; Hypertension - physiopathology; Investigative techniques of hemodynamics; Investigative techniques, diagnostic techniques (general aspects); Male; Medical sciences; Middle Aged; Nitroglycerin - pharmacology; Nitroprusside - pharmacology; Obesity - complications; Obesity - physiopathology; Ultrasonography; Vasodilation - drug effects; Vasodilation - physiology; Vasodilator Agents - pharmacology; Human; Hypertension; Obesity; Nutrition disorder; Cardiovascular disease; Nitrates; nitrate; Coronary heart disease; Vascular disease; Microcirculation; coronary microcirculation; Atherosclerosis; flow-mediated dilation; Nutritional status
• ISSN: 1079-5642; 1524-4636; 1524-4636
• DOI: 10.1161/ATVBAHA.107.147991

OBJECTIVES—We hypothesized that simultaneous presence of obesity and hypertension activates adaptive vascular mechanisms affecting dilations of human coronary arterioles. METHODS AND RESULTS—Agonist-induced dilations were assessed in isolated pressurized coronary arterioles from patients (n=38) who underwent cardiac surgery. Among normotensives we found that dilations to bradykinin (BK) and the NO-donor, sodium-nitroprusside (SNP) were reduced in obese subjects (BK, 10 mol/L, lean:90±4%, obese:64±7%; SNP, 10 mol/L, lean:89±7%, obese:76±5%). However, among hypertensives, both BK- and SNP-induced dilations were significantly enhanced in obese patients, when compared with lean individuals (BK, lean:71±7%, obese:85±3%; SNP, lean:60±6%, obese:83±2%). Correspondingly, in hypertensive patients, but not in those of normotensives, a positive correlation was found between body mass index (BMI) and BK-induced (P=0.036, r=0.46), and also SNP-evoked (P=0.031, r=0.44) coronary dilations. Moreover, in additional 55 hypertensive patients flow-mediated (FMD) and nitroglycerin (NTG)-induced dilations of the brachial artery were assessed. In obese hypertensive individuals, FMD- and NTG-induced dilations were greater (FMD:6.2±0.7%, NTG:17.2±0.9%), than in lean hypertensive patients (FMD:3.7±0.6%, NTG:13.6±1.1%). Correspondingly, FMD- and NTG-induced dilations were positively correlated with BMI (P=0.020, r=0.31 and P=0.033, r=0.29, respectively). CONCLUSIONS—These findings are the first to suggest that obesity may lead to activation of adaptive vascular mechanisms to enhance the dilator function of coronary and peripheral arterial vessels in hypertensive patients.