摘要
为研究地塞米松对肝硬变大鼠离体血管反应性的影响及其机制。将大鼠胆总管结扎 2 8～ 30 d形成胆源性肝硬变 ,给予地塞米松 0 .2 5 m g/ (kg.d)或安慰剂皮下注射 ,连续 7d。观察离体主动脉环对苯肾上腺素和乙酰胆碱的反应 ,以及各组大鼠主动脉中 2种一氧化氮合酶 (i NOS和 e NOS)的表达。发现对苯肾上腺素的反应 ,肝硬变处理组高于肝硬变组 ,但仍低于对照组 ,左旋硝基精氨酸甲酯 (L- NAME)处理消除了肝硬变处理组和肝硬变组的差异。对乙酰胆碱的反应 ,肝硬变处理组和肝硬变组均高于对照组 ,但两组之间无差异。免疫组化显示肝硬变处理组主动脉中 i NOS表达低于肝硬变组。结果表明 :地塞米松处理抑制了肝硬变时主动脉中 i NOS的表达 ,减少了 NO的产量 。
The effect of dexamethasone (Dex) on vascular reactivity of isotaled aortic rings from biliary cirrhotic rats was investigated. Cirrhosis was induced by chronic bile duct ligation of 28 30 days. Either a Dex administration of 0 25 mg/(kg·d) or placebo was given by subcutaneous injection for 7 consecutive days. The responses of isolated aortic rings to phenylephrine and acetylcholine were observed. The expression of iNOS and eNOS was detected by immunohistochemistry. The vasoconstriction to phenylephrine of aortic rings from cirrhosis+Dex group was higher than cirrhosis group, but still lower than the control. Pretreatment with L NAME could abolish the difference between cirrhosis+Dex group and cirrhosis group. The vasodilatation to acetylcholine of cirrhosis+Dex group and cirrhosis group was higher than the control, but no difference was found between the two groups. The expression of iNOS in aorta from cirrhosis+Dex group was lower than in the cirrhosis group. It was concluded that Dex administration could inhibit the iNOS expression in the aorta of cirrhotic rats, decrease the NO production and so increase the vascular reactivity to vasoconstrictor.
出处
《华中科技大学学报（医学版）》
CAS
CSCD
北大核心
2002年第3期298-300,共3页
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
基金
湖北省科委科研基金资助项目 (No.911A2 6 0 2)
