Putcha L, Cintron N M, Vanderploeg J M, Chen Y, Habis J, Adler J
Technology Life Sciences Division: SD/4 Biomedical Laboratories Branch, NASA/Johnson Space Center, Houston, TX 77058.
Aviat Space Environ Med. 1988 Apr;59(4):306-8.
Physiological changes that occur during exposure to weightlessness may induce alterations in blood flow to the liver. Estimation of hepatic blood flow (HBF) using ground-based weightlessness simulation models may provide insight into functional changes of the liver in crewmembers during flight. In the present study HBF, indirectly estimated by indocyanine green (ICG) clearance, is compared in 10 subjects during the normal ambulatory condition and antiorthostatic (-6 degrees) bed rest. Plasma clearance of ICG was determined following intravenous administration of a 0.5-mg.kg-1 dose of ICG to each subject on two separate occasions, once after being seated for 1 h and once after 24 h of head-down bed rest. After 24 h of head-down bed rest, hepatic blood flow did not change significantly from the respective control value.
暴露于失重状态期间发生的生理变化可能会引起肝脏血流的改变。利用地面失重模拟模型估算肝血流量（HBF），可能有助于深入了解飞行期间机组人员肝脏的功能变化。在本研究中，通过吲哚菁绿（ICG）清除率间接估算的HBF，在10名受试者处于正常活动状态和头低位（-6度）卧床休息时进行了比较。在两个不同时间点，对每位受试者静脉注射0.5 mg·kg-1剂量的ICG后，测定ICG的血浆清除率，一次是在坐位1小时后，另一次是在头低位卧床休息24小时后。头低位卧床休息24小时后，肝血流量与各自的对照值相比无显著变化。
