Stangeland L, Grong K, Lekven J
Clin Physiol. 1984 Jun;4(3):209-19. doi: 10.1111/j.1475-097x.1984.tb00115.x.
Selective beta 1- or beta 2-adrenergic blockade was achieved by practolol or IPS 339, respectively, in cats with acute ligation of a coronary artery. During blockade, heart rate was kept constant by atrial pacing and blood pressure reduction was prevented by aortic clamping. Regional myocardial blood flow was measured by the distribution of 15 micron labelled microspheres. Practolol slightly reduced epicardial blood flow in ischaemic myocardium, while blood flow in border and normally perfused myocardium remained unchanged. Following IPS 339, myocardial tissue flow increased in normally perfused myocardium, on average by 37% in the endocardium and 30% in the epicardium. No changes occurred in the other regions. The flow changes brought about by IPS 339 were unrelated to haemodynamic changes, and the coronary vascular resistance was reduced. These results are indicative of coronary vasodilation related to beta 2-adrenergic receptor blockade and was confined to well-oxygenated areas surrounding the acutely ischaemic zone.
在急性结扎冠状动脉的猫中，分别用心得宁或IPS 339实现选择性β1或β2肾上腺素能阻断。在阻断期间，通过心房起搏使心率保持恒定，并通过主动脉夹闭防止血压降低。通过15微米标记微球的分布来测量局部心肌血流量。心得宁使缺血心肌的心外膜血流量略有减少，而边缘心肌和正常灌注心肌的血流量保持不变。给予IPS 339后，正常灌注心肌的心肌组织血流量增加，心内膜平均增加37%，心外膜增加30%。其他区域未发生变化。IPS 339引起的血流变化与血流动力学变化无关，且冠状动脉血管阻力降低。这些结果表明与β2肾上腺素能受体阻断相关的冠状动脉扩张，且局限于急性缺血区周围的充分氧合区域。
