Hutchison S J, Glantz S A, Zhu B Q, Sun Y P, Chou T M, Chatterjee K, Deedwania P C, Parmley W W, Sudhir K
Division of Cardiology, University of California, San Francisco, Moffitt Hospital, USA.
J Am Coll Cardiol. 1998 Nov;32(5):1463-7. doi: 10.1016/s0735-1097(98)00217-4.
We sought to determine the effects of secondhand smoke (SHS) exposure on vascular reactivity in newborn and infant rats.
Secondhand smoke exposure increases cardiovascular risk. Secondhand smoke-induced endothelial dysfunction has been demonstrated in older teenagers and young adults. We have previously shown in adult rabbits that SHS induces atherogenesis and endothelial dysfunction. The effects of SHS on vascular function in the offspring of SHS-exposed mothers and in infants are unknown.
In this study the effects of in-utero (21 days) and neonatal (28 days) exposure to SHS were examined in 80 rats, 4 weeks of age, in a 2-by-2 design study. Rats were exposed to sidestream smoke in smoking chambers. Aortic rings were excised and isometric force responses to phenylephrine, acetylcholine, A23187 and nitroglycerin were studied in organ baths.
Neonatal SHS exposure reduced animal weight (p=0.009). In-utero exposure increased the sensitivity (decreased the EC50) of aortic rings to phenylephrine (p < 0.0005), as did neonatal exposure (p=0.01). Maximal contraction to phenylephrine was reduced by in-utero exposure (p=0.04). In-utero SHS exposure reduced maximal endothelium-dependent relaxation to acetylcholine (p=0.04) and increased the EC50 (p=0.05), suggesting impaired sensitivity to acetylcholine. In-utero exposure decreased the sensitivity (increased the EC50) to the endothelium-independent vasodilator nitroglycerin (p=0.003).
Secondhand smoke has detrimental effects on vascular smooth muscle function in the newborn.
我们试图确定二手烟暴露对新生和幼年大鼠血管反应性的影响。
二手烟暴露会增加心血管疾病风险。二手烟导致的内皮功能障碍已在青少年和年轻成年人中得到证实。我们之前在成年兔中发现，二手烟会诱发动脉粥样硬化和内皮功能障碍。二手烟对二手烟暴露母亲的后代及婴儿血管功能的影响尚不清楚。
在本研究中，采用2×2设计，对80只4周龄大鼠进行子宫内（21天）和新生儿期（28天）二手烟暴露影响的研究。将大鼠置于吸烟室内暴露于侧流烟雾中。切除主动脉环，在器官浴槽中研究其对去氧肾上腺素、乙酰胆碱、A23187和硝酸甘油的等长力反应。
新生儿期二手烟暴露使动物体重减轻（p = 0.009）。子宫内暴露增加了主动脉环对去氧肾上腺素的敏感性（降低了半数有效浓度，EC50）（p < 0.0005），新生儿期暴露也有此作用（p = 0.01）。子宫内暴露使对去氧肾上腺素的最大收缩反应降低（p = 0.04）。子宫内二手烟暴露降低了对乙酰胆碱的最大内皮依赖性舒张反应（p = 0.04），并增加了EC50（p = 0.05），提示对乙酰胆碱的敏感性受损。子宫内暴露降低了对非内皮依赖性血管舒张剂硝酸甘油的敏感性（增加了EC50）（p = 0.003）。
二手烟对新生儿血管平滑肌功能有有害影响。
