Kamimori G H, Hoyt R W, Eddington N D, Young P M, Durkot M J, Forte V A, Brunhart A E, Lugo S, Cymerman A
Department of Behavioral Biology, Walter Reed Army Medical Institute of Research, Washington, DC 20307-5100, USA.
Aviat Space Environ Med. 1995 Mar;66(3):247-50.
The pharmacokinetics of caffeine and cardio-green (ICG) were examined in four micro swine at sea level (SEA) and following 21 d continuous exposure to 4600 m (ALT) in a hypobaric chamber. Caffeine (84.7 mg) and ICG (10 mg) were administered as separate intravenous boluses and sequential blood samples collected.
Caffeine clearance significantly (p < 0.05) increased in ALT (96.8 +/- 20.0 ml.min-1) as compared to SEA (53.6 +/- 24.8 ml.min-1), demonstrating that liver function increased in ALT. There was no significant change in the ratio of primary metabolites to caffeine, suggesting that the increase in clearance was not due to a change in the rate of caffeine metabolism. ICG clearance significantly increased in ALT (179.8 +/- 57.4 ml.min-1) as compared to SEA (84.4 +/- 28.9 ml.min-1) indicating that hepatic blood flow (HBF) increased.
These results demonstrate that chronic exposure to 4600 m increases the clearance of caffeine and ICG in the micro swine model and suggests that the increase in caffeine clearance is related to HBF.
在4只微型猪中，于海平面（SEA）以及在低压舱连续暴露于4600米高度（ALT）21天后，检测咖啡因和心绿（ICG）的药代动力学。分别静脉推注咖啡因（84.7毫克）和ICG（10毫克），并采集连续的血样。
与SEA组（53.6±24.8毫升·分钟⁻¹）相比，ALT组（96.8±20.0毫升·分钟⁻¹）咖啡因清除率显著增加（p<0.05），表明在ALT环境下肝功能增强。咖啡因主要代谢产物与咖啡因的比例无显著变化，提示清除率的增加并非由于咖啡因代谢速率改变所致。与SEA组（84.4±28.9毫升·分钟⁻¹）相比，ALT组（179.8±57.4毫升·分钟⁻¹）ICG清除率显著增加，表明肝血流量（HBF）增加。
这些结果表明，在微型猪模型中，长期暴露于4600米高度会增加咖啡因和ICG的清除率，且咖啡因清除率的增加与肝血流量有关。
