Department of Medicine, University of Wisconsin, Madison, Wisconsin.
William S. Middleton Memorial Veterans Affairs Medical Center, Madison, Wisconsin.
Am J Physiol Regul Integr Comp Physiol. 2020 Nov 1;319(5):R566-R574. doi: 10.1152/ajpregu.00325.2019. Epub 2020 Sep 9.
Asthma and obstructive sleep apnea (OSA) are highly prevalent chronic conditions, and both are associated with systemic hypertension. Additionally, asthma and OSA reciprocally interact, mutually exacerbating each other. In this study, we tested the effect of allergen-induced lower airway inflammation and concurrent chronic intermittent hypoxia (CIH) on systemic blood pressure (BP), pulmonary function, and proinflammatory cytokines, in a rat model. Brown Norway rats were exposed to 43 days of normoxia (NORM) or CIH, concurrent with weekly house dust mite (HDM) challenges. BP was measured 1 day after the last HDM challenge. On , pulmonary function was tested, and blood for Th-2 and Th-1 cytokine levels was collected. HDM significantly increased mean ( = 0.002), systolic ( = 0.003), and diastolic ( = 0.004) BP compared with saline-challenged controls. Higher mean BP significantly correlated to increased total respiratory system resistance ( = 0.266, = 0.002), driven by an association with parenchymal tissue dampening ( = 0.166, = 0.016). HDM relative to saline-challenged controls increased the expression of serum IL-6 ( = 0.008), but no relationships of systemic BP with IL-6 or any other cytokines were found. CIH did not alter the allergen-induced responses on BP, although it tended to increase the expression of serum IL-6 ( = 0.06) and monocyte chemoattractant protein-1 (MCP-1, = 0.09), regardless of HDM challenge. Chronic allergen-induced airway inflammation results in systemic hypertension that is correlated to the degree of distal airway obstruction induced by the allergen. These effects do not appear to be explained by the associated systemic inflammation.
哮喘和阻塞性睡眠呼吸暂停（OSA）是高度流行的慢性疾病，两者都与系统性高血压有关。此外，哮喘和 OSA 相互作用，相互加剧。在这项研究中，我们在大鼠模型中测试了过敏原引起的下呼吸道炎症和并发的慢性间歇性低氧（CIH）对全身血压（BP）、肺功能和促炎细胞因子的影响。褐鼠暴露于 43 天的常氧（NORM）或 CIH 中，同时每周接受屋尘螨（HDM）挑战。在最后一次 HDM 挑战后 1 天测量 BP。第 28 天，测试肺功能，并采集血液以检测 Th-2 和 Th-1 细胞因子水平。与盐水对照相比，HDM 显著增加了平均（ = 0.002）、收缩压（ = 0.003）和舒张压（ = 0.004）。更高的平均 BP 与总呼吸系统阻力的增加显著相关（ = 0.266， = 0.002），这与实质组织衰减有关（ = 0.166， = 0.016）。与盐水对照相比，HDM 增加了血清中 IL-6 的表达（ = 0.008），但未发现全身 BP 与 IL-6 或任何其他细胞因子之间存在关系。尽管 CIH 倾向于增加血清 IL-6（ = 0.06）和单核细胞趋化蛋白-1（MCP-1， = 0.09）的表达（无论是否存在 HDM 挑战），但它并未改变过敏原引起的 BP 反应。慢性过敏原引起的气道炎症导致全身高血压，这与过敏原引起的远端气道阻塞程度相关。这些影响似乎与相关的全身炎症无关。
