Reduction in Visceral Adiposity is Highly Related to Improvement in Vascular Endothelial Dysfunction among Obese Women Abbott, Abbott Park, Illinois, USA). Levels of high-density C-reactive protein (hsCRP) were measured by nephelometry using BNII (Dade Behring, Liederbach, Germany) with a mini- mum detection concentration of 0.0175 mg/dL. Homeostasis Model Assessment (HOMA) scores were calculated to evaluate insulin resistance.10 Evaluation of vascular endothelial function Pulse wave analysis using the provocative phar- macological test was performed by administering salbutamol or nitroglycerin (NTG) to determine VED. Pulse wave analysis A pulse wave is composed of two waves, i.e., an aortic wave produced when the left ventricle contracts and a reflected wave produced when the aortic wave is reflected from peripheral vessels. The velocity of the reflected waves is increased when the arterial walls are stiff. Accordingly, in cases with stiffened arteries, systolic pressure aug- mentation occurs during the systolic phase. Based on this principle, radial artery pressure was measured using a high-fidelity micromanometer (SphygmoCor, Medical ECONET Co., Sydney, Australia). In practice, the artery is compressed between a sensor and the underlying structures, and, thus, the intra-arterial pressure is transmitted through the arterial wall to the sensor. Data were collected directly using a portable computer. After 20 sequential waveforms had been acquired, in- tegral software was used to generate an averaged peripheral waveform and a corresponding central waveform. Further analysis was conducted to determine AIx and the ascending aortic pressure, as described previously.7,11,12 AIx was defined as the difference between the first (P1) and second (P2) peaks of the central arterial waveform, ex- pressed as a percentage of pulse pressure.13,14 In this study, repeated pulse wave analyses at one-week intervals in ten non-obese volunteers showed a coefficient of variance (CV) of 1.4 ± 2.3 % for AIx. Measurements of aix after salbutamol or ntg admini- stration AIx was evaluated after administering nitrogly- cerin or salbutamol, which induce endothelial- independent vasodilation and endothelial-depen- dent vasodilation, respectively. AIx was deter- mined during the peak response which occurred 3 minutes after administering 0.6 mg of nitrogly- cerin. The difference in AIx before and after this administration was measured and is depicted as AIx-NTG. Twenty-five minutes after admini- stering nitroglycerin, 2.5 mg of nebulized salbuta- mol (Ventolin nebules), which acts on vascular endothelial cells through the L-arginine-NO path- way, was administered by inhalation using a mask. Thiry minutes later, the pulse wave an- alysis was again carried out to measure AIx. The difference between AIx before and after salbuta- mol administration was then determined and is depicted as AIx-Salb.5,7,11 The dosage and timing of the administration of these drugs were based on pilot studies and previous experience. Pilot studies confirmed that 15 minutes was sufficient to allow NTG-induced hemodynamic changes to return to baseline, but that a longer period was required for salbutamol. Therefore, NTG was always administered first, and followed by salbutamol 25 minutes later. Diet and exercise program For effective weight control, a diet and exercise program was utilized, and subjects were ed- ucated regarding living habits. To maintain a low calorie/low fat diet, subjects received 1,000 kcal per day during the program. Initially, subjects ex- ercised for half an hour a day, 3 times a week. The length and frequency of exercise were then in- creased every other week, reaching 40-60 minutes a day and 4-5 times a week. Subject compliance was evaluated at every visit by examining the dietary diary and weight loss log. Subjects were administered 20 mg of fluoxetine daily, as well as a thermogenic agent (pseudoephedrine 60 mg, theolan 100 mg) as a supplementary measure. To avoid side-effects, drugs were administered for the first 4 weeks only. Three months later, physi- cal examinations, obesity measurements, and pulse wave analysis were repeated. Statistical analysis Yonsei Med J Vol. 46, No. 4, 2005