Regional circulations in experimental coarctation of the aorta in conscious dogs.
Regional circulations in experimental coarctation of the aorta in conscious dogs.
复制标题
清醒狗实验性主动脉缩窄的区域循环。
DOI：
10.1097/00004872-198506000-00014
复制
发表时间：
1985
影响因子：
4.9
通讯作者：
Spadone,JC
中科院分区：
文献类型：
--
作者：
Liard,JF;Spadone,JC
用放射性微球测量35只有意识的狗在胸降主动脉狭窄后不同时间（1小时至28天）的局部血流量。狭窄近端平均动脉压适度升高。远端动脉压在狭窄后立即降至控制值以下，然后在28天内逐渐恢复到收缩前的值。在主动脉收缩1和6小时后，血浆肾素活性增加了6倍，并在4天内保持显著升高。血容量无明显变化。在一些近端压力升高的血管床中，早期血流明显增加，主要是在心肌、脑、骨骼肌和骨骼。然而，28天后，暴露在近端压力下的大多数组织的血流量明显减少。在这一阶段，与假手术对照组相比，心肌、大脑、肌肉、皮肤和骨骼的血管传导明显降低。经远端动脉压灌注的几个血管床在28天后也显示出明显的流量下降，尤其是小肠、皮肤、骨骼肌和骨骼。在这一阶段，小肠、肌肉、皮肤和骨骼的血管导度下降。因此，狗的主动脉缩窄的特征是血管阻力的晚期全身性增加，延伸到从未暴露于动脉压力增加或血流量增加的组织。这些研究结果表明，在缩窄性高血压患者中，全身血管收缩剂的影响超过了局部机制对局部循环的控制。
Regional blood flows were measured with radioactive microspheres in 35 conscious dogs at various times (between 1 h and 28 days) after creation of a stenosis of the descending thoracic aorta. Mean arterial pressure increased moderately proximal to the stenosis. Distally, arterial pressure decreased below control values immediately after stenosis, then returned gradually toward preconstriction values over 28 days. Plasma renin activity increased sixfold, after aortic constriction of 1 and 6 h, and remained significantly elevated for four days. Blood volume did not change significantly. In some of the vascular beds exposed to the elevated proximal pressure, significant increases in blood flow were noted in the early stages, mainly in the myocardium, the brain, the skeletal muscles and the bones. After 28 days, however, blood flows were significantly reduced in most tissues exposed to the proximal pressure. At this stage, vascular conductance was significantly decreased in the myocardium, the brain, the muscles, the skin and the bones as compared with a sham-operated control group. Several vascular beds perfused by the distal arterial pressure also showed a significant fall in flow after 28 days, notably the small intestine, the skin, the skeletal muscles and the bones. At that stage, vascular conductance was decreased in the small intestine, the muscles, the skin and the bones. Thus, aortic coarctation in dogs was characterized by a late generalized increase in vascular resistance extending to tissues which were never exposed to increased arterial pressure nor to an increased blood flow. These findings suggest that a systemic vasoconstrictor influence overrides local mechanisms in the control of regional circulations in coarctation hypertension.