Costa L R, Seahorn T L, Moore R M, Oliver J L, Hosgood G L
Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge 70803, USA.
Am J Vet Res. 2001 Sep;62(9):1381-6. doi: 10.2460/ajvr.2001.62.1381.
To determine concentrations of nitric oxide (NO) in plasma and bronchoalveolar lavage fluid (BALF) and localize nitric oxide synthesis in the lungs of horses with summer pasture-associated obstructive pulmonary disease (SPAOPD).
7 adult horses with SPAOPD and 6 clinically normal adult horses.
Severity of SPAOPD was determined by use of clinical scores, change in intrapleural pressure (APpl) during tidal breathing, cytologic analysis of BALF, and histologic evaluation of lung specimens obtained during necropsy. Nitric oxide concentrations in plasma, BALF and epithelial lining fluid (ELF) were determined by use of a chemiluminescent method. Inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT) were localized in formalin-fixed lung specimens by use of immunohistochemical staining, and nicotinamide adenine dinucleotide phosphate diaphorase (NADPHd) activity was localized in cryopreserved specimens by use of histochemical staining.
Plasma concentration of NO in affected horses was slightly but not significantly greater than concentration in nonaffected horses. Nitric oxide concentrations in BALF or ELF did not differ between groups. Immunoreactivity of iNOS in bronchial epithelial cells of 3 of 5 lung lobes was greater in horses with SPAOPD, compared with nonaffected horses. However, staining for NT and NADPHd activity did not differ between groups.
Expression of iNOS was greater in bronchial epithelial cells of horses with SPAOPD, compared with nonaffected horses, suggesting that NO may play a role in amplifying the inflammatory process in the airways of horses with this disease.
测定患有夏季牧场相关性阻塞性肺病（SPAOPD）马匹的血浆和支气管肺泡灌洗液（BALF）中一氧化氮（NO）的浓度，并确定肺内一氧化氮的合成部位。
7匹患有SPAOPD的成年马和6匹临床正常的成年马。
通过临床评分、潮式呼吸期间胸膜腔内压（APpl）的变化、BALF的细胞学分析以及尸检时获取的肺标本的组织学评估来确定SPAOPD的严重程度。采用化学发光法测定血浆、BALF和上皮衬液（ELF）中的一氧化氮浓度。通过免疫组织化学染色在福尔马林固定的肺标本中定位诱导型一氧化氮合酶（iNOS）和硝基酪氨酸（NT），并通过组织化学染色在冷冻保存的标本中定位烟酰胺腺嘌呤二核苷酸磷酸黄递酶（NADPHd）活性。
患病马匹的血浆NO浓度略高于未患病马匹，但差异不显著。两组之间BALF或ELF中的一氧化氮浓度没有差异。与未患病马匹相比，5个肺叶中有3个肺叶的支气管上皮细胞中iNOS的免疫反应性在患有SPAOPD的马匹中更高。然而，两组之间NT染色和NADPHd活性没有差异。
与未患病马匹相比，患有SPAOPD的马匹支气管上皮细胞中iNOS的表达更高，这表明NO可能在加剧患此病马匹气道的炎症过程中起作用。
