- 作者: Kwok-Keung Lam, Shung-Tai Ho, Mao-Hsiung Yen
- 作者服務機構: Graduate Institute of Medical Sciences, school of Medicine and Department of Pharmacology ,National Defense Medical Center, Taipei and Chu-Tung Veterans Hospitals, Taiwan
- 中文摘要: --
- 英文摘要: sham group. In addition, there were significant increasesin superoxide anion production in aortic tissue and sig-nificant decreases in plasma nitric oxide levels in the Ovxgroup. Furthermore, BH4 contents in the aorta in the Ovxgroup were significantly decreased compared with thesham group. In conclusion, the present study demon-strates that the impairment of vascular reactivity wasfound in the ovariectomized rats. The possible mecha-nism of this defect may have resulted from the deficiencyof available BH4. Thus, this study may provide a noveltherapeutic strategy for the treatment of postmenopaus-al cardiovascular disorders.The goal of the present study is to investigate the role oftetrahydrobiopterin (BH4) in the vascular response inovariectomized rats. Rats were randomly assigned totwo groups: (1) sham group: sham-operated female rats,and (2)Ovx group: rats were ovariectomized. Our resultshave shown that the plasma 17β-estradiol levels in theOvx group at the end of the experiment were significant-ly lower than in the sham group. Vasoreactivity assessedwith intact aortic rings indicated that the phenylephrine-induced vasocontractile response to aortic rings from theOvx group was greater than that of the sham group. Incontrast, the vasodilator responses to acetylcholine andL-arginine (L-Arg) in the sham group were significantlygreater than in the Ovx group. Differences in vasoreactiv-ity in denuded aorta between the two groups were notnoted. Moreover, exogenous BH4 significantly restoredL-Arg-induced vasodilator responses in the Ovx group.However, this improvement effect was not found in the
- 中文關鍵字: --
- 英文關鍵字: Superoxide anion, Nitric oxide, Tetrahydrobiopterin, Vascular reactivity, Estrogen, Ovariectomy