Li Qi-hao, Dong Zhao-xing, Zhang Tao, Chai Yan-ling, Zhong Hong, Wang Ying, Lei Wen, Hai Bing, Li Zhen-kun, Wu Wen-juan, Rao Ming-qing
Department of Respiratory Medicine, The 2nd Affiliated Hospital, Kunming Medical College, Kunming, Yunnan 650101, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2007 Oct;30(10):761-6.
To explore the protective effects of hypercapnia on acute lung injury (ALI) and the possible mechanisms.
Twenty-four healthy New Zealand white rabbits were involved in this study, and randomly divided to three groups, a control group, a therapeutic group, and a prophylactic group (n=8, each). Lipopolysaccharide (1 mg/kg) was injected intravenously to establish the ALI model. Blood gas analysis and artery pressure were monitored. IL-8 and TNF-alpha in the serum and bronchoalveolar lavage fluid (BALF), wet weight/dry weigh (W/D), index of quantitative assessment of histological lung injury (IQA), myeloperoxidase (MPO) and malondialdehyde (MDA) activity in the lung tissue were measured. Apoptosis index of neutrophils were determined.
(1) The mean artery pressure, heart rate, PaCO2, and PaO2/FiO2 changed in the ALI model of the therapeutic group and the prophylactic group [(79+/-6) mm Hg (1 mm Hg=0.133 kPa), (180+/-10)/min, (99+/-13) mm Hg, 250+/-26, (80+/-9) mm Hg, (181+/-12)/min, (95+/-11) mm Hg, 241+/-56, respectively]. In the control group, they were (66+/-10) mm Hg, (139+/-13)/min, (31+/-4) mm Hg, 182+/-35, respectively. The differences were significant compared with the control group (t=4.05, 26.32, 5.36, 28.15, 12.54, 11.07, 16.13, 12.36, P<0.05, 0.01). (2) The levels of W/D, MPO, and MDA in the therapeutic group and the prophylactic group were 1.98+/-0.28, 1.87+/-0.30, (6.1+/-1.6) U/g, (5.8+/-1.5) U/g, (20+/-5) mg/L, (19+/-4) mg/L; while in the control group, they were [2.43+/-0.26, (9.0+/-1.3) U/g, (36+/-8) mg/L] respectively. The difference was significant (t=11.07, 24.46, 2.35, 9.63, 12.34, 25.32, P<0.05, 0.01). (3) The levels of IL-8 and TNF-alpha in the serum and BALF and the apoptosis index in the three groups were (50+/-8) ng/ml, (103+/-49) ng/ml, (94+/-16) ng/ml, (44+/-9) ng/ml, (38+/-9)%, (56+/-5)%, (49+/-7) ng/ml, (96+/-50) ng/ml, (91+/-14) ng/ml, (39+/-6) ng/ml, (39+/-10)%, (55+/-10)%, (91+/-43) ng/ml, (177+/-60) ng/ml, (162+/-15) ng/ml, (67+/-7) ng/ml, (19+/-7)%, (43+/-7)%, respectively. The difference was significant among the three groups (t=7.12, 5.55, 7.30, 3.93, 13.08, 8.00, P<0.05, 0.01 respectively). (4) The apoptosis index of neutrophils was negatively correlated with the levels of IL-8 in the serum and BALF (r=-0.73, -0.72, -0.52, -0.64, -0.73, -0.56, all P<0.05), and the levels of TNF-alpha in the serum and BALF (r=-0.57, -0.78, -0.69, -0.75, -0.82, -0.84, all P<0.05).
Hypercapnia does not affect hemodynamics and has protective effects on ALI.
探讨高碳酸血症对急性肺损伤（ALI）的保护作用及其可能机制。
24只健康新西兰白兔参与本研究，随机分为三组，即对照组、治疗组和预防组（每组n = 8）。静脉注射脂多糖（1 mg/kg）建立ALI模型。监测血气分析和动脉压。检测血清及支气管肺泡灌洗液（BALF）中的IL-8和TNF-α、肺组织湿重/干重（W/D）、组织学肺损伤定量评估指数（IQA）、髓过氧化物酶（MPO）和丙二醛（MDA）活性。测定中性粒细胞凋亡指数。
（1）治疗组和预防组ALI模型的平均动脉压、心率、PaCO₂及PaO₂/FiO₂分别为[（79±6）mmHg（1 mmHg = 0.133 kPa），（180±10）/min，（99±13）mmHg，250±26，（80±9）mmHg，（181±12）/min，（95±11）mmHg，241±56]。对照组分别为（66±10）mmHg，（139±13）/min，（31±4）mmHg，182±35。与对照组相比差异有统计学意义（t = 4.05，26.32，5.36，28.15，12.54，11.07，16.13，12.36，P < 0.05，0.01）。（2）治疗组和预防组的W/D、MPO及MDA水平分别为1.98±0.28，1.87±0.30，（6.1±1.6）U/g，（5.8±1.5）U/g，（20±5）mg/L，（19±4）mg/L；而对照组分别为[2.43±0.26，（9.0±1.3）U/g，（36±8）mg/L]。差异有统计学意义（t = 11.07，24.46，2.35，9.63，12.34，25.32，P < 0.05，0.01）。（3）三组血清及BALF中IL-8和TNF-α水平及凋亡指数分别为（50±8）ng/ml，（103±49）ng/ml，（94±16）ng/ml，（44±9）ng/ml，（38±9）%，（56±5）%，（49±7）ng/ml，（96±50）ng/ml，（91±14）ng/ml，（39±6）ng/ml，（39±10）%，（55±10）%，（91±43）ng/ml，（177±60）ng/ml，（162±15）ng/ml，（67±7）ng/ml，（19±7）%，（43±7）%。三组间差异有统计学意义（t = 7.12，5.55，7.30，3.93，13.08，8.00，P分别< 0.05，0.01）。（4）中性粒细胞凋亡指数与血清及BALF中IL-8水平呈负相关（r = -0.73，-0.72，-0.52，-0.64，-0.73，-0.56，均P < 0.05），与血清及BALF中TNF-α水平呈负相关（r = -0.57，-0.78，-0.69，-0.75，-0.82，-0.84，均P < 0.05）。
高碳酸血症不影响血流动力学，对ALI有保护作用。
