Venugopalan C S, Beadle R E, Seahorn T L, Holmes E P
Department of Veterinary Physiology, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA.
Vet Res Commun. 1998 Nov;22(7):493-503. doi: 10.1023/a:1006131217140.
The response of parenchymal strips from guinea-pig lungs to tracheobronchial lavage fluid (TBLF) collected from 8 normal horses and from 8 affected with summer pasture-associated obstructive pulmonary disease (SPAOPD) was determined. TBLF was collected during the summer (July) and winter (February) seasons. The serum/TBLF urea nitrogen ratio was used to standardize the mediator concentration in the TBLF. Four strips were used from each guinea-pig. The first strip did not receive any antagonist and served as the control. The second, third and fourth strips received antagonists of PGE2, LTD4 and PAF, respectively at 10(-6) mol/L for 30 min. The tissues were then precontracted with a dose of histamine (10(-5) mol/L) and their responses to 1 ml of TBLF were determined. The study showed that TBLF obtained in the summer from unaffected horses produced a significantly greater relaxation than that from the affected horses, whereas TBLF obtained in the winter from unaffected or affected horses did not cause a significantly different degree of relaxation. Among the antagonist-treated strips, only those exposed to the PGE2 blocker showed a significant reduction in the relaxation caused by TBLF obtained in the summer from SPAOPD horses. This suggests that PGE2 is an important mediator present in the summer in the TBLF from horses affected with SPAOPD.
测定了豚鼠肺实质条对从8匹正常马和8匹患有夏季牧场相关阻塞性肺病（SPAOPD）的马采集的气管支气管灌洗液（TBLF）的反应。TBLF在夏季（7月）和冬季（2月）采集。血清/TBLF尿素氮比值用于标准化TBLF中的介质浓度。每只豚鼠使用4条组织条。第一条组织条不接受任何拮抗剂，作为对照。第二条、第三条和第四条组织条分别接受浓度为10(-6)mol/L的PGE2、LTD4和PAF拮抗剂处理30分钟。然后用一定剂量的组胺（10(-5)mol/L）使组织条预收缩，并测定它们对1ml TBLF的反应。研究表明，夏季从未受影响的马获得的TBLF产生的舒张作用明显大于受影响的马，而冬季从未受影响或受影响的马获得的TBLF引起的舒张程度没有显著差异。在接受拮抗剂处理的组织条中，只有那些暴露于PGE2阻滞剂的组织条，对夏季从患有SPAOPD的马获得的TBLF引起的舒张作用有显著降低。这表明PGE2是夏季患有SPAOPD的马的TBLF中的一种重要介质。
