ABSTRACT
BACKGROUND: Ferulic acid (FA) is a naturally occurring nutritional compound. Although it has been shown to have antihypertensive effects, its effects on vascular function have not been intensively established. The aim of this study was to assess the vasoreactivity of FA in chronic two-kidney, one-clip (2K1C) renal hypertensive rats. METHODS: Hypertension was induced in 2K1C rats by clipping the left renal artery and age-matched rats that received a sham treatment served as a control. Thoracic aortas were mounted in tissue baths to measure isometric tension. The effects of FA on vasodilatory responses were evaluated based on contractile responses induced by phenylephrine in the aortic rings obtained from both 2K1C and sham rats. Basal nitric oxide (NO) bioavailability in the aorta was determined by the contractile response induced by NO synthase inhibitor N (G)-nitro-l-arginine methyl ester (l-NAME). RESULTS: FA induced concentration-dependent relaxation responses which were greater in 2K1C hypertensive rats than in sham-clipped control rats. This relaxation induced by FA was partially blocked by the removal of endothelium or by pretreating with l-NAME. l-NAME-induced contractile responses were augmented by FA in 2K1C rats, while no significant differences were noted in sham rats. FA improved acetylcholine-induced endothelium-dependent vasodilation in 2K1C rats, but not in sham rats. The simultaneous addition of hydroxyhydroquinone significantly inhibited the increase in acetylcholine-induced vasodilation by FA. CONCLUSION: These results suggest that FA restores endothelial function by altering the bioavailability of NO in 2K1C hypertensive rats. The results explain, in part, the mechanism underlying the vascular effects of FA in chronic renal hypertension.
ABSTRACT
OBJECTIVES: Coronary artery disease (CAD) and abdominal aortic aneurysms (AAA) commonly coexist. However, each disease treatment complicates the management of the other. In this study, we evaluate whether a simultaneous operation of AAA repair and off pump coronary artery bypass (OPCAB) would be safe and acceptable, compared with either procedure alone. SUBJECTS AND METHODS: We retrospectively reviewed all patients who underwent simultaneous AAA repair and OPCAB (AAA/OPCAB, n=18), compared AAA repair alone (AAA, n=239) and OPCAB alone (OPCAB, n=137) from June 1999 to December 2003. There were no significant differences with regard to age or gender, but the AAA/OPCAB group had significantly larger aneurysms (60.6 vs. 53.2 mm) and significantly lower ejection fractions (EF) (54.9 vs. 60.3%). RESULTS: The patients in the AAA/OPCAB group underwent a significantly longer operative time than AAA, OPCAB (403 vs. 360, 296 minutes, respectively), there was significantly greater blood loss (726 vs. 426, 462 ml), and more transfusion required (8.13 vs. 1.69, 2.8 units). The number of bypass grafts in AAA/OPCAB group (1-5 per patients) was significantly smaller (1.78 vs. 2.93). The AAA/OPCAB patients had a significantly longer hospital stay than the AAA (38 vs. 22 days), but was not significantly longer than the OPCAB. There were no significant differences with regard to the morbidity and mortality rate among the three groups. CONCLUSION: This study suggests that the simultaneous operation of AAA and OPCAB can be done with the same morbidity and mortality as independent surgical procedures.
