Sakuma T, Hida M, Nambu Y, Osanai K, Toga H, Takahashi K, Ohya N, Inoue M, Watanabe Y
Department of Thoracic Surgery, Medical Research Institute, Kanazawa Medical University, Uchinada, Ishikawa, Japan.
Jpn J Pharmacol. 2001 Feb;85(2):161-6. doi: 10.1254/jjp.85.161.
Because it was still uncertain whether a stimulation of beta1-adrenoceptors accelerated alveolar fluid clearance in hyperoxic lung injury, the effect of denopamine, a selective beta1-adrenergic agonist, on alveolar fluid clearance was determined in rats exposed to 93% oxygen for 48 and 56 h. Alveolar fluid clearance was measured by the progressive increase in the concentration of Evans blue labeled albumin instilled into the alveolar spaces over 1 h at 37 degrees C in isolated rat lungs. The principle results were as follows: 1) Although lung water volume increased in rats exposed to hyperoxia for 48 and 56 h, basal alveolar fluid clearance did not change for up to 56 h; 2) Denopamine increased alveolar fluid clearance in rats exposed to hyperoxia as well as in rats without exposure to hyperoxia; 3) Denopamine primarily increased amiloride-insensitive alveolar fluid clearance in rats exposed to hyperoxia; 4) The potency of denopmaine was similar to that of terbutaline, a selective beta2-adrenergic agonist. In summary, denopamine is a potent stimulator of alveolar fluid clearance in rats exposed to hyperoxia.
由于β1肾上腺素能受体的刺激是否能加速高氧性肺损伤时的肺泡液体清除仍不确定，因此在暴露于93%氧气48小时和56小时的大鼠中，测定了选择性β1肾上腺素能激动剂多巴胺对肺泡液体清除的影响。通过在37℃下，在离体大鼠肺中，1小时内肺泡腔内注入伊文思蓝标记白蛋白的浓度逐渐增加来测量肺泡液体清除。主要结果如下：1）尽管暴露于高氧48小时和56小时的大鼠肺水含量增加，但基础肺泡液体清除在长达56小时内没有变化；2）多巴胺增加了暴露于高氧的大鼠以及未暴露于高氧的大鼠的肺泡液体清除；3）多巴胺主要增加了暴露于高氧的大鼠中对氨氯地平不敏感的肺泡液体清除；4）多巴胺的效力与选择性β2肾上腺素能激动剂特布他林相似。总之，多巴胺是暴露于高氧的大鼠肺泡液体清除的有效刺激剂。
