Jynge P, Blankson H, Schjøtt J, Holten T, Oksendal A N
Department of Pharmacology and Toxicology, Faculty of Medicine, University of Trondheim, Norway.
Invest Radiol. 1995 Mar;30(3):173-80. doi: 10.1097/00004424-199503000-00007.
The authors studied cardiac contractile responses during coronary bolus perfusion, as in coronary angiography, in three species and related the responses to the bolus content of electrolytes and to patterns of cardiac electrolyte regulation.
Isolated, paced hearts from the rat, guinea pig, and rabbit were subjected to coronary perfusion in the global mode with recording of left ventricular developed pressure during exposure (< 7.5 seconds) and recovery (30 seconds).
In series 1 of the experiments, the perfusate reduction to one fifth of normal Ca, Na, K, Mg, and Ca/Na/K/Mg, and the removal of all ions, led to the following percentage changes in left ventricular developed pressure: rat -64, +84, -38, +7, +40, and +79; guinea pig -43, +48, +18, +5, +28, and +37; and rabbit -32, +60, +14, +4, +22, and +33.
Except for K reduction, inducing negative inotropy in the rat but positive inotropy in the guinea pig and the rabbit, the three species responded similarly. Thus, changes in left ventricular developed pressure were related to changes in direction and rate of the sarcomal Na-Ca exchange. In series 2 of the experiments, iohexol (150 mg I/mL) +/- minor electrolyte additives were studied. Additives with Na 30 mmol/L only or with Na, Ca, K, and Mg carefully balanced reduced positive and negative inotropic responses in all three species.
作者研究了在冠状动脉团注灌注（如冠状动脉血管造影术中）时三种物种的心脏收缩反应，并将这些反应与团注中的电解质含量以及心脏电解质调节模式相关联。
对大鼠、豚鼠和兔的离体起搏心脏进行全心模式的冠状动脉灌注，在暴露（<7.5秒）和恢复（30秒）期间记录左心室舒张末压。
在实验系列1中，灌注液中钙、钠、钾、镁以及钙/钠/钾/镁降至正常水平的五分之一，且去除所有离子后，左心室舒张末压的百分比变化如下：大鼠分别为-64、+84、-38、+7、+40和+79；豚鼠分别为-43、+48、+18、+5、+28和+37；兔分别为-32、+60、+14、+4、+22和+33。
除了钾减少在大鼠中导致负性肌力作用，而在豚鼠和兔中导致正性肌力作用外，这三种物种的反应相似。因此，左心室舒张末压的变化与肌小节钠-钙交换的方向和速率变化有关。在实验系列2中，研究了碘海醇（150 mg I/mL）+/-少量电解质添加剂。仅含30 mmol/L钠或钠、钙、钾和镁仔细平衡的添加剂可降低所有三种物种的正性和负性肌力反应。
