肾灌流量减少造影剂可能从几个方面对肾灌流量产生不良影响。首先,对心脏产生负性肌力作用和外周血管扩张效应。致使收缩压明显下降并伴随肾灌流量减少。此点可能是导致肾功能损害的肾前性机理。在双时相时,肾血管床本身的血流量对造影剂产生的反应是值得注意的。一部分血管床血流量增多,但更多的是特久性下降。第二时相可能是由于血管收缩或继发于造影剂在肾小管内的渗透性所引起的肾实质压力增高。另外,造影剂使红细胞产生僵硬等形态学改变,此不良作用可能减少肾脏和其它器官的微循环 Reduced renal perfusion flow contrast media may have several adverse effects on renal perfusion. First, the heart produces negative inotropic effects and peripheral vasodilation effects. Resulting in a significant reduction of systolic blood pressure accompanied by decreased renal perfusion. This may be the prerenal mechanism leading to impaired renal function. At double phases, the response of the renal blood vessel itself to the contrast medium is noteworthy. Part of the vascular bed blood flow increased, but more is the decline of special durability. The second phase may be due to vasoconstriction or secondary to the permeability of contrast medium in the renal tubular caused by increased renal parenchymal pressure. In addition, contrast agents make morphological changes such as red blood cell stiffness, this adverse effect may reduce the microcirculation of the kidneys and other organs