Tan Rachel H H, Thatcher Craig D, Buechner-Maxwell Virginia, Christmann Undine, Crisman Mark V, Werre Stephen R
Department of Veterinary Clinical Sciences, School of Veterinary and Biomedical Sciences, James Cook University, Townsville, QLD 4810, Australia.
Am J Vet Res. 2010 Dec;71(12):1500-7. doi: 10.2460/ajvr.71.12.1500.
To measure the ascorbic acid (AA) concentration in bronchoalveolar lavage fluid (BALF) and cellular glutathione peroxidase (cGPx) activity in RBCs and WBCs from peripherally obtained blood and in cells from BALF to determine whether differences existed between the 2 major redox systems in recurrent airway obstruction (RAO)-affected and -nonaffected (control) horses and between systemic and local pulmonary responses in the glutathione redox system.
16 adult horses in pairs: 8 healthy (control) and 8 RAO-affected horses.
Physical examination data and biological samples were collected from horses before (remission), during, and after (recovery) environmental challenge with dusty straw and hay. At each stage, BALF cell AA concentration and RBC, WBC, and BALF cell cGPx activity were measured.
Compared with control horses, RAO-affected horses had significantly higher cGPx activity in RBCs at all points and in WBCs during remission and challenge. The BALF cell cGPx activity was higher in RAO-affected horses during recovery than during remission The BALF cell AA concentration did not differ significantly in control horses at any point, but total and free AA concentrations were significantly lower in RAO-affected horses during the challenge period than during remission and recovery periods.
High cGPx activity suggested this redox system was upregulated during exposure to dusty straw and hay to combat oxidative stress, as AA was depleted in RAO-affected horses. The relative delay and lack of comparative increase in cGPx activity within the local environment (represented by BALF cells), compared with that in RBCs and WBCs, might contribute to disease in RAO-affected horses.
测量支气管肺泡灌洗液（BALF）中的抗坏血酸（AA）浓度，以及外周血红细胞（RBC）和白细胞（WBC）与BALF细胞中的细胞谷胱甘肽过氧化物酶（cGPx）活性，以确定复发性气道阻塞（RAO）患马和未患马（对照）的两个主要氧化还原系统之间是否存在差异，以及谷胱甘肽氧化还原系统中全身和局部肺部反应之间是否存在差异。
16匹成年马，两两配对：8匹健康马（对照）和8匹患RAO的马。
在给马用多尘的稻草和干草进行环境刺激之前（缓解期）、期间和之后（恢复期）收集体格检查数据和生物样本。在每个阶段，测量BALF细胞AA浓度以及RBC、WBC和BALF细胞的cGPx活性。
与对照马相比，患RAO的马在所有时间点的RBC中以及缓解期和刺激期的WBC中的cGPx活性均显著更高。患RAO的马在恢复期的BALF细胞cGPx活性高于缓解期。对照马在任何时间点的BALF细胞AA浓度均无显著差异，但患RAO的马在刺激期的总AA浓度和游离AA浓度显著低于缓解期和恢复期。
高cGPx活性表明，在接触多尘的稻草和干草期间，该氧化还原系统被上调以对抗氧化应激，因为患RAO的马体内AA被耗尽。与RBC和WBC相比，局部环境（以BALF细胞为代表）中cGPx活性的相对延迟和缺乏相应增加可能是患RAO的马发病的原因。
