Ramanathan K B, Raina S, Banka V S, Bodenheimer M M, Helfant R H
Circulation. 1978 Jan;57(1):47-52. doi: 10.1161/01.cir.57.1.47.
In 14 dogs the effects on regional tension (Walton-Brodie gauges) and length (mercury-in-silastic) following 50% reduction (52.9 +/- 2.1) in coronary flow for two hours and reperfusion afterwards for one hour were addressed. Within five minutes of partial coronary occlusion, ejection tension in the ischemic zone decreased to 36.3 +/- 7.2% (P less than 0.001) and total tension to 64.4 +/- 5.7% of control (P less than 0.001) while phasic segment length increased to 165.2 +/- 16.3% control. No further significant changes in regional tension or length were observed throughout the two hour period of partial occlusion. Ejection tension remained positive and segment length maintained systolic shortening during the ejection phase throughout the period of occlusion. Following reperfusion, ejection tension in the ischemic zone increased from 35.1 +/- 5.9 to 87.0 +/- 22.0% (P less than 0.05) and total tension increased from 56.6 +/- 5.4 to 70.2 +/- 7.2% (P less than 0.02) while segment length decreased from 149.3 +/- 6.5 to 105.7 +/- 5.7% (P less than 0.001) within five to 15 min of reperfusion. The improvement in both regional tension development and segment length shortening was maintained throughout the one hour period of reperfusion. No significant changes were seen in the nonischemic zone. The present experimental study suggests that partial coronary occlusion producing a 50% reduction in coronary blood flow results in regional contractile changes. These changes are reversible at least twice as long as those following complete occlusion.
在14只犬中，研究了冠状动脉血流减少50%（52.9±2.1）持续两小时并随后再灌注一小时对局部张力（Walton-Brodie测量仪）和长度（硅橡胶汞柱）的影响。在冠状动脉部分闭塞的五分钟内，缺血区的射血张力降至对照值的36.3±7.2%（P<0.001），总张力降至对照值的64.4±5.7%（P<0.001），而相位节段长度增加至对照值的165.2±16.3%。在部分闭塞的两小时期间，未观察到局部张力或长度有进一步的显著变化。在整个闭塞期间，射血张力保持为正，节段长度在射血期保持收缩期缩短。再灌注后，缺血区的射血张力从35.1±5.9%增加至87.0±22.0%（P<0.05），总张力从56.6±5.4%增加至70.2±7.2%（P<0.02），而节段长度在再灌注的5至15分钟内从149.3±6.5%降至105.7±5.7%（P<0.001）。在整个再灌注的一小时期间，局部张力发展和节段长度缩短的改善均得以维持。非缺血区未见显著变化。本实验研究表明，冠状动脉部分闭塞导致冠状动脉血流减少50%会引起局部收缩变化。这些变化至少比完全闭塞后引起的变化可逆两倍。
