Gerber K H, Higgins C B
Invest Radiol. 1982 May-Jun;17(3):292-8.
Contrast materials may alter coronary blood flow (CBF) by a direct vasodilating action or indirectly by changing determinants of myocardial oxygen requirements (MVO2). The current study compared the vasodilatory actions of ionic (Renografin 76, R76) and nonionic contrast materials (iohexol and metrizamide) after direct injection into the coronary and femoral circulation of anesthetized dogs. R76 did not cause a significantly greater increase in CBF compared with nonionic materials in spite of causing significantly greater increases in osmolality of blood in the coronary sinus. Concomitant with the peak increase in CBF, the ionic materials caused sharp decrease in peak left ventricular (LV) systolic pressure and dp/dt, while the nonionic materials increased these major determinants of MVO2. In contradistinction to the effects on CBF, ionic contrast material caused substantially and significantly greater increase in femoral blood flow, compared with the nonionic materials. In conclusion, these studies infer that the increase in CBF with contrast materials involves both indirect vascular and metabolic actions, while the increase in FBF is due to a direct vascular action.
造影剂可通过直接血管舒张作用或通过改变心肌氧需求（MVO2）的决定因素间接改变冠状动脉血流（CBF）。本研究比较了离子型（泛影葡胺76，R76）和非离子型造影剂（碘海醇和甲泛葡胺）直接注入麻醉犬的冠状动脉和股循环后的血管舒张作用。尽管R76导致冠状窦血液渗透压显著升高，但与非离子型造影剂相比，其并未使CBF显著增加。伴随CBF峰值增加，离子型造影剂导致左心室（LV）收缩压峰值和dp/dt急剧下降，而非离子型造影剂则增加了MVO2的这些主要决定因素。与对CBF的影响相反，与非离子型造影剂相比，离子型造影剂使股血流量显著增加。总之，这些研究推断造影剂使CBF增加涉及间接血管和代谢作用，而股血流量增加是由于直接血管作用。
