Barman S A, Ardell J L, Taylor A E
Department of Pharmacology and Toxicology, Medical College of Georgia, Augusta 30912, USA.
Respir Physiol. 1995 Feb;99(2):249-57. doi: 10.1016/0034-5687(94)00090-m.
The effects of phorbol myristate acetate (PMA) induced lung injury on the pulmonary and systemic blood flow contributions to the trachea and main bronchi (upper airways) were assessed in anesthetized dogs by injecting 15 microns radiolabeled microspheres into the right and left heart, respectively. Upper airway blood flow was studied in lungs given the following treatments: (1) PMA; (2) PMA in lungs pretreated with the thromboxane synthetase inhibitor OKY-046, and (3) PMA in lungs pretreated with the antioxidant catalase. After microsphere injections, the tracheal cartilage, tracheal muscle-mucosa, and main bronchi were excised. The results of this study indicate that under normal conditions, tracheal mucosa [33-52 ml.min-1.(100 g)-1] and tracheal cartilage [18-27 ml.min-1.(100 g)-1] blood flow is primarily systemic while both the systemic [12-18 ml.min-1.(100 g)-1] and pulmonary [6-12 ml.min-1.(100 g)-1] circulations contribute substantial amounts of blood flow to the main bronchi. PMA significantly decreased the systemic blood flow contribution to the tracheal cartilage and muscle-mucosa, and both the systemic and pulmonary blood flow contributions to the main bronchi to less than 50% of control values, an effect that was inhibited by catalase, but not by OKY-046. These results suggest that the effect of PMA-induced lung injury on the pulmonary and systemic blood flow contributions to the upper airways is at least partially mediated by oxygen radical production, probably hydrogen peroxide (H2O2), but not by the production of the arachidonic acid metabolite thromboxane.
通过分别向麻醉犬的右心和左心注射15微米放射性标记微球，评估佛波酯肉豆蔻酸酯乙酸盐（PMA）诱导的肺损伤对气管和主支气管（上呼吸道）肺循环和体循环血流贡献的影响。在接受以下处理的肺中研究上呼吸道血流：（1）PMA；（2）用血栓素合成酶抑制剂OKY - 046预处理的肺中的PMA；以及（3）用抗氧化剂过氧化氢酶预处理的肺中的PMA。微球注射后，切除气管软骨、气管肌 - 黏膜和主支气管。本研究结果表明，在正常情况下，气管黏膜[33 - 52毫升·分钟-1·（100克）-1]和气管软骨[18 - 27毫升·分钟-1·（100克）-1]的血流主要来自体循环，而体循环[12 - 18毫升·分钟-1·（100克）-1]和肺循环[6 - 12毫升·分钟-1·（100克）-1]均对主支气管贡献大量血流。PMA显著降低了体循环对气管软骨和肌 - 黏膜的血流贡献，以及体循环和肺循环对主支气管的血流贡献，使其降至对照值的50%以下，过氧化氢酶可抑制这一效应，但OKY - 046不能。这些结果表明，PMA诱导的肺损伤对上呼吸道肺循环和体循环血流贡献的影响至少部分是由氧自由基产生介导的，可能是过氧化氢（H2O2），而非花生四烯酸代谢产物血栓素的产生。
