著者
Tomio Okamura Masashi Tawa Ayman Geddawy Takashi Shimosato Hirotaka Iwasaki Haruo Shintaku Yuichi Yoshida Masahiro Masada Kazuya Shinozaki Takeshi Imamura
出版者
The Japanese Pharmacological Society
雑誌
Journal of Pharmacological Sciences (ISSN:13478613)
巻号頁・発行日
vol.124, no.1, pp.76-85, 2014-01-20 (Released:2014-01-18)
参考文献数
41
被引用文献数
10 21

Deficiency of tetrahydrobiopterin (BH4) in the vascular tissue contributes to endothelial dysfunction through reduced eNOS activity and increased superoxide anion (O2−) generation in the insulin-resistant state. We investigated the effects of atorvastatin, a 3-hydroxyl-3-methylglutaryl coenzyme A (HMG CoA) reductase inhibitor; amlodipine, a calcium antagonist; and their combination on blood pressure, arterial relaxation and contraction, and vascular oxidative stress in aortas of high fructose–fed rats. Oral administration of atorvastatin for 8 weeks did not significantly lower blood pressure, but normalized angiotensin II–induced vasoconstriction and endothelial function in the fructose-fed rats. Atorvastatin treatment of fructose-fed rats increased vascular BH4 content, which was associated with an increase in endothelial NO synthase activity as well as a reduction in endothelial O2− production. On the other hand, administration of amlodipine did not affect the angiotensin II–induced vasoconstriction and endothelial function, but normalized the elevated blood pressure in the fructose-fed rats. The combined treatment did not show synergistic but additive beneficial effects. The present study suggests that combined therapy of HMG-CoA reductase inhibitors and calcium antagonists prevents functional vascular disorders in the insulin-resistant state, possibly resulting in the protection against or delay of development of hypertension, vascular dysfunction in diabetes, and thereafter atherosclerosis.