• 作者： 周崇龍; 陳幸一; 徐剛; 李敏輝; 汪大衛
• 作者服務機構： 國防醫學院生理學科; 三軍總醫院內科學科
• 中文摘要： Phorbol myristate acetate（PMA）在動物模型上可以成功地引發急性肺損傷。學者認為從被 PMA 激活的中性白血球所釋放出的氧游離基在這類肺損傷中紛演一個重要角色。本篇研究是探討 dimethylthiourea（DMTU）對此類肺損傷的保護效用。DMTU 是一種對 OH 和的強清除劑。PMA 灌注到離體鼠肺後，肺動脈壓升高 37.8±3.9 mmHg，肺重增加 6.2±1.2 gm，肺沖洗液白蛋白濃度為102.0±22.9 mg/dl。若事先以DMTU（100 mM）處理，則肺動脈壓只升高 4.6±0.8 mmHg（p＜0.001），肺重增加 0.3±0.1 gm (p＜0.01），肺沖洗液白蛋白濃度為 25.3±1.7 mg/dl（p＜0.01）。 體外實驗也證明 DMTU 減少被 PMA 激活的中性白血球所釋放出的冷光，且呈劑量反應曲線。這些結果顯示DMTU 減輕 PMA 所引發之急性肺損傷，其機轉可能是透過抑制肺高血壓，和防止 PMA 對肺血管通透性所造成的損傷。
• 英文摘要： Acute pulmonary edema can be induced by phorbol myristate acetate (PMA). Oxygen radicalsreleased from the neutrophils have been considered to play an important role in the pathogenesis of PMA-induced pulmonary edema. In the present experiment, we studied the effect of dimethylthiourea (DMTU)on PMA-induced pulmonary injuries in isolated perfused lungs of rats. DMTU is a potent scavenger of thehydroxyl radical and hydrogen peroxide. PMA infusion into the isolated lung increased pulmonary arterialpressure (△PAP) by 37.8±3.9 mmHg. The lung weight gain (LWG) and lavage albumin concentration (LAC)amounted to 6.2±1.2 g and 102.0±22.9 mg/dl, respectively. DMTU (100 mM) pretreatment significantlyreduced the PAP increase (△PAP = 4.6±0.8 mmHg, p ＜0.001), LWG (0.3±0.1 g, p ＜0.01) and LAC (25.3±1.7 mg/dl, p ＜0.01). Additional in vitro experiments demonstrated that DMTU depressed the chemilu-minescence released from neutrophils activated by PMA (17.9 ± 2.6 mV.min to 2.6 ± 0.5 mV.min, p ＜0.01). The results suggest that DMTU, a scavenger of toxic radicals, decreases the lung edema through bothattenuation of pulmonary hypertension and protection of vascular permeability from PMA injury.
• 中文關鍵字： dimethylthiourea; phorbol myristate acetate; lung injury
• 英文關鍵字： --