Riva E, Hearse D J
Cardiovascular Research, Rayne Institute, St Thomas' Hospital, London, England.
Ann Thorac Surg. 1991 Oct;52(4):987-92. doi: 10.1016/0003-4975(91)91265-w.
We describe an isolated, perfused preparation for neonatal rat hearts to assess the relationship between extracellular calcium and (1) cardiac function and (2) contractile stability over 2 hours of perfusion. Neonatal (3 to 5 days old) rat hearts (n = 6 per group) were perfused for 30 minutes (Langendorff) with oxygenated buffer (37 degrees C) containing 1.4 mmol/L calcium (control period) and 90 minutes with buffer containing 0.5, 0.8, 1.0, 1.2, 1.4, 1.8, or 2.5 mmol/L calcium. Upon changing from 1.4 mumol/L to either a higher or low calcium concentration there were no significant changes in left ventricular developed pressure, heart rate, or coronary flow. However, left ventricular developed pressure progressively deteriorated in a time-dependent and calcium-dependent manner. Thus, after 90 minutes, developed pressure fell to 18% +/- 2%, 27% +/- 3%, 41% +/- 5%, 47% +/- 8%, 55% +/- 10%, 64% +/- 5% and 76% +/- 4% of its initial value with 0.5, 0.8, 1.0, 1.2, 1.4, 1.8, and 2.5 mmol/L calcium. In conclusion, in studies with the neonatal rat heart, extracellular calcium concentrations in the range of 1.8 to 2.5 mmol/L are recommended.
我们描述了一种用于新生大鼠心脏的离体灌注制备方法，以评估细胞外钙与（1）心脏功能和（2）灌注2小时内收缩稳定性之间的关系。新生（3至5日龄）大鼠心脏（每组n = 6）先用含1.4 mmol/L钙的含氧缓冲液（37℃）灌注30分钟（Langendorff法），然后用含0.5、0.8、1.0、1.2、1.4、1.8或2.5 mmol/L钙的缓冲液灌注90分钟。从1.4 μmol/L钙浓度变为较高或较低钙浓度时，左心室舒张末压、心率或冠脉流量均无显著变化。然而，左心室舒张末压以时间和钙浓度依赖性方式逐渐恶化。因此，90分钟后，当钙浓度分别为0.5、0.8、1.0、1.2、1.4、1.8和2.5 mmol/L时，舒张末压分别降至其初始值的18%±2%、27%±3%、41%±5%、47%±8%、55%±10%、64%±5%和76%±4%。总之，在新生大鼠心脏研究中，建议细胞外钙浓度范围为1.8至2.5 mmol/L。
