Waldenstrõm A P, Hjalmarson A C
Acta Med Scand Suppl. 1976;587:141-9. doi: 10.1111/j.0954-6820.1976.tb05876.x.
Isolated working rat hearts were made ischemic by introducing a one-way aortic ball valve. After the ischemic period the hearts were perfused in a retrograde non-working way for 30 min. Flow rates, glycogen, ATP, and creatine-phosphate went down during the time of ischemia, whereas tissue lactate accumulated. For shorter periods of ischemia these values were normalized but after 30 min of ischemia the hearts seemed to be irreversibly damaged. There was a leakage of GOT, GPT, LDH, and CPK from all hearts when ischemic from 5 to 30 min. Different factors that might be of importance for the degree of ischemic injury were tested. The injury tended to be more severe at higher heart rates. Addition of adrenaline 10(-6)M resulted in excessive myocardial damage. A variation of pH from 7.1 to 7.7 did not alter the effects of the ischemic injury. One group of rats were injected with adrenaline for 8 weeks to simulate chronic stress. When hearts from these rats were made ischemic they were more prone to fail compared to controls. The failing hearts, on the other hand, had a lower leakage of enzymes, possibly due to a less severe myocardial damage. A high mechanical performance and a normal noradrenaline content of the hearts are key factors for the development of myocardial infarction, as indicated by this study.
通过置入单向主动脉球囊瓣膜使离体工作大鼠心脏缺血。缺血期过后，心脏以逆行非工作方式灌注30分钟。在缺血期间，血流量、糖原、三磷酸腺苷（ATP）和磷酸肌酸下降，而组织乳酸则积聚。对于较短的缺血期，这些值会恢复正常，但缺血30分钟后，心脏似乎受到了不可逆的损伤。当缺血5至30分钟时，所有心脏都出现了谷草转氨酶（GOT）、谷丙转氨酶（GPT）、乳酸脱氢酶（LDH）和肌酸磷酸激酶（CPK）的泄漏。对可能影响缺血性损伤程度的不同因素进行了测试。心率较高时，损伤往往更严重。添加10(-6)M肾上腺素会导致过度的心肌损伤。pH值从7.1变化到7.7并未改变缺血性损伤的影响。一组大鼠注射肾上腺素8周以模拟慢性应激。与对照组相比，这些大鼠的心脏缺血时更容易衰竭。另一方面，衰竭的心脏酶泄漏较少，这可能是由于心肌损伤较轻。如本研究所示，心脏的高机械性能和正常的去甲肾上腺素含量是心肌梗死发生发展的关键因素。
