Effects of thyroid state on venous compliance and left ventricular performance in rats.
Effects of thyroid state on venous compliance and left ventricular performance in rats.
复制标题
甲状腺状态对大鼠静脉顺应性和左心室性能的影响。
DOI：
10.1152/ajpheart.1988.254.1.h81
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Goldman,S
中科院分区：
文献类型：
--
作者：
Gay,RG;Raya,TE;Lancaster,LD;Lee,RW;Morkin,E;Goldman,S
通过评估大鼠的外周静脉循环和左心室 (LV) 收缩和舒张性能来研究甲状腺功能减退、正常和甲状腺功能亢进大鼠的心血管系统。在开胸大鼠中测量心脏指数（CI）和容量负荷期间的 CI。与对照组相比，甲状腺功能减退大鼠的心率、主动脉压、左室收缩压、左室压力一阶导数 (LV dP/dt)、CI 和容量负荷期间 CI 均降低。左心室压力-容积关系右移，肌肉僵硬度不变，左心室舒张时间延长。对照大鼠的平均循环充盈压 (MCFP) 从 7.6 +/- 0.2 mmHg 降低至 6.3 +/- 0.2。这与无压力血管容量减少 11% 和总血容量减少 12% 相关，但静脉顺应性没有变化。甲状腺功能亢进大鼠的心率、左心室收缩压、左心室 dP/dt、CI 和容量负荷期间 CI 增加。左心室僵硬度增加，但肌肉僵硬度和左心室舒张度没有变化。与对照大鼠的 3.20 +/- 0.09 ml.mmHg-1.kg-1 相比，MCFP 增加至 9.5 +/- 0.3 mmHg，静脉顺应性降低至 2.65 +/- 0.12。无应力血管容量和总血容量没有变化。总之，甲状腺功能亢进大鼠的左心室收缩功能增强，舒张功能改变，再加上静脉循环的变化，导致静脉回流增加，从而增加心输出量。甲状腺功能减退大鼠的左心室收缩和舒张功能均发生改变。当与静脉循环的变化相结合时，这些变化会导致心输出量减少。
The cardiovascular system of hypothyroid, normal, and hyperthyroid rats was studied by evaluation of the peripheral venous circulation and left ventricular (LV) systolic and diastolic performance in rats. Cardiac index (CI) and CI during a volume load were measured in open-chest rats. When compared with control, hypothyroid rats showed a decrease in heart rate, aortic pressure, LV systolic pressure, first derivative for LV pressure (LV dP/dt), CI, and CI during a volume load. LV pressure-volume relation was shifted to the right, muscle stiffness was unchanged, and LV relaxation was prolonged. There was a decrease in mean circulatory filling pressure (MCFP) to 6.3 +/- 0.2 from 7.6 +/- 0.2 mmHg in control rats. This was associated with an 11% decrease in unstressed vascular volume and 12% decrease in total blood volume but no change in venous compliance. In hyperthyroid rats there was an increase in heart rate, LV systolic pressure, LV dP/dt, CI, and CI during a volume load. LV chamber stiffness was increased, but muscle stiffness and LV relaxation were unchanged. There was an increase in MCFP to 9.5 +/- 0.3 mmHg and a decrease in venous compliance to 2.65 +/- 0.12 compared with 3.20 +/- 0.09 ml.mmHg-1.kg-1 in control rats. Unstressed vascular volume and total blood volume were unchanged. In conclusion, hyperthyroid rats have augmented LV systolic function and altered diastolic function which, combined with changes in the venous circulation, result in increased venous return and thus cardiac output. In hypothyroid rats both LV systolic and diastolic function are altered. When combined with changes of the venous circulation the changes result in a decrease in cardiac output.