Department of Kinesiology, University of Texas Arlington, Arlington, TX, USA.
Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA.
Sci Rep. 2021 Sep 10;11(1):18094. doi: 10.1038/s41598-021-97732-3.
Severe burns result in cardiovascular dysfunction, but responses in the peripheral vasculature are unclear. We hypothesize that severe burns disturb arterial contractility through acute changes in adrenergic and cholinergic receptor function. To address this, we investigated the changes in carotid artery contractility and relaxation following a severe burn. Thirty-four adult Sprague-Dawley male rats received a 40% total body surface area (TBSA) scald burn and fluid resuscitation using the Parkland formula. Control animals received sham burn procedure. Animals were serially euthanized between 6 h and 14 days after burn and endothelium-intact common carotid arteries were used for ex vivo force/relaxation measurements. At 6 h after burn, carotid arteries from burned animals demonstrated a > 50% decrease in cumulative dose-responses to norepinephrine (p < 0.05) and to 10 M angiotensin II (p < 0.05). Notably, pre-constricted carotid arteries also demonstrated reduced relaxation responses to acetylcholine (p < 0.05) 6 h after burn, but not to sodium nitroprusside. Histologic examination of cross-sectional planes revealed significant increases in carotid artery wall thickness in burned rats at 6 h versus 3 days, with increased collagen expression in tunica media at 3 days (p < 0.05). Carotid artery dysfunction occurs within 6 h after severe burn, demonstrating decreased sensitivity to adrenergic- and angiotensin II-induced vasoconstriction and acetylcholine-induced relaxation.
严重烧伤会导致心血管功能障碍，但外周血管的反应尚不清楚。我们假设严重烧伤通过急性改变肾上腺素能和胆碱能受体功能来干扰动脉收缩性。为了解决这个问题，我们研究了严重烧伤后颈动脉收缩性和松弛性的变化。34 只成年 Sprague-Dawley 雄性大鼠接受 40%总体表面积（TBSA）的烫伤烧伤和使用 Parkland 公式进行液体复苏。对照动物接受假烧伤手术。动物在烧伤后 6 小时至 14 天之间被连续安乐死，并用内皮完整的颈总动脉进行离体力/松弛测量。烧伤后 6 小时，烧伤动物的颈动脉对去甲肾上腺素（p<0.05）和 10 M 血管紧张素 II（p<0.05）的累积剂量反应显示出超过 50%的降低。值得注意的是，预收缩的颈动脉在烧伤后 6 小时对乙酰胆碱的松弛反应也降低（p<0.05），但对硝普钠没有。横断面的组织学检查显示，烧伤大鼠在 6 小时与 3 天相比，颈动脉壁厚度显著增加，3 天时中膜胶原表达增加（p<0.05）。严重烧伤后 6 小时内发生颈动脉功能障碍，表现为对肾上腺素能和血管紧张素 II 诱导的血管收缩以及乙酰胆碱诱导的松弛的敏感性降低。
