Su M Y, Wang Z, Roth G M, Lao X, Samoszuk M K, Nalcioglu O
Department of Radiological Sciences, University of California, Irvine 92714, USA.
Magn Reson Med. 1996 Dec;36(6):868-77. doi: 10.1002/mrm.1910360609.
The effects of three physiologically different vasomodulators, angiotensin II (a vasoconstrictor), hydralazine (a vasodilator), and histamine (a permeability modulator), on the pharmaco-kinetics of entry of small molecules (measured by Gd-DTPA concentration) into normal and abnormal tissue were studied in rats implanted with R3230 AC tumors. Sequential dynamic Gd-DTPA-enhanced MRI studies, one before and one after vasomodulator administration, were performed, and the signal intensities of various tissues analyzed. Angiotensin II (6 micrograms/kg) reduced blood flow in tumors, but increased it in muscles. Hydralazine (5 mg/kg) reduced blood flow in tumors, kidneys, and livers, and slowed Gd-DTPA clearance from tumors, livers, and muscles. Histamine (25 micrograms/kg) increased renal blood flow, hastening Gd-DTPA clearance causing reduced measurable blood flow in tumors and muscles. By simultaneously monitoring the effects in various tissues, the pharmacokinetic effect of each drug in the entire body could be obtained.
在植入R3230 AC肿瘤的大鼠中，研究了三种生理作用不同的血管调节剂——血管紧张素II（一种血管收缩剂）、肼屈嗪（一种血管扩张剂）和组胺（一种通透性调节剂）对小分子（通过钆喷酸葡胺浓度测量）进入正常组织和异常组织的药代动力学的影响。在给予血管调节剂之前和之后分别进行了连续动态钆喷酸葡胺增强磁共振成像研究，并分析了各种组织的信号强度。血管紧张素II（6微克/千克）可降低肿瘤中的血流量，但增加肌肉中的血流量。肼屈嗪（5毫克/千克）可降低肿瘤、肾脏和肝脏中的血流量，并减缓钆喷酸葡胺从肿瘤、肝脏和肌肉中的清除。组胺（25微克/千克）可增加肾血流量，加快钆喷酸葡胺的清除，导致肿瘤和肌肉中可测量的血流量减少。通过同时监测各种组织中的效应，可以获得每种药物在全身的药代动力学效应。
