Vatner S F, Pagani M, Rutherford J D, Millard R W, Manders W T
Am J Physiol. 1978 Mar;234(3):H244-52. doi: 10.1152/ajpheart.1978.234.3.H244.
The effects of intravenous infusion of nitroglycerin (NTG), 8 and 32 microgram/kg.min for 7 min, and of sublingual NTG, 1.2 mg, were examined on direct and continuous measurements of systemic, coronary, and regional hemodynamics, left ventricular (LV) dimensions, pressures, and myocardial contractility in conscious dogs. NTG induced sustained reductions in LV dimensions and transient increases in heart rate and dP/dt, and decreases in mean arterial pressure. Initially NTG increased cardiac output and flows to the coronary, mesenteric, renal, and iliac beds, while systemic and regional vascular resistances fell. Later, cardiac output, cardiac work, and mesenteric and iliac flows fell significantly below control, and significant vasoconstriction in the systemic as well as mesenteric, iliac, and coronary beds was observed at a time when LV end-diastolic dimensions were still significantly reduced. Peripheral vasoconstriction was not observed with systemic NTG in deafferented dogs or when NTG, 1 microgram/kg.min, was infused intra-arterially into the iliac bed. Thus, systemic NTG induces a biphasic response consisting of initial arteriolar vasodilation followed by vasoconstriction in the mesenteric, iliac, coronary and systemic beds, which is presumably due to longer lasting effects on preload and to secondary reflex responses to the drug.
在清醒犬中，对静脉输注硝酸甘油（NTG）（8和32微克/千克·分钟，持续7分钟）以及舌下含服NTG（1.2毫克）后全身、冠状动脉和局部血流动力学、左心室（LV）尺寸、压力和心肌收缩力的直接连续测量结果进行了研究。NTG导致LV尺寸持续减小，心率和dP/dt短暂增加，平均动脉压降低。最初，NTG增加心输出量以及流向冠状动脉、肠系膜、肾和髂血管床的血流量，同时全身和局部血管阻力下降。随后，心输出量、心脏作功以及肠系膜和髂血管床的血流量显著低于对照水平，并且在LV舒张末期尺寸仍显著减小的时候，观察到全身以及肠系膜、髂和冠状动脉床出现明显的血管收缩。在去传入神经的犬中，全身给予NTG未观察到外周血管收缩，或者当以1微克/千克·分钟的速度将NTG动脉内输注到髂血管床时也未观察到外周血管收缩。因此，全身给予NTG会引发双相反应，包括最初的小动脉血管舒张，随后是肠系膜、髂、冠状动脉和全身血管床的血管收缩，这可能是由于对前负荷的持续影响以及对该药物的继发反射反应所致。
