Influence of heart rate on left ventricular performance in conscious dogs.
Influence of heart rate on left ventricular performance in conscious dogs.
复制标题
心率对清醒狗左心室性能的影响。
DOI：
10.1161/01.res.61.3.455
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发表时间：
1987
影响因子：
20.1
通讯作者：
O'Rourke,RA
中科院分区：
文献类型：
--
作者：
Freeman,GL;Little,WC;O'Rourke,RA
在8只清醒的犬上研究了心房起搏对左心室收缩末期压力-容积关系的影响。其中6只犬在肾脏完整时进行了研究，2只犬在自主神经阻滞后进行了研究，分别给予2 mg/kg普萘洛尔和0.2 mg/kg阿托品。用微压计测量左心室压力，并从3个超声正交维度确定左心室容积。在控制心率和心房起搏100、120、140、160、180和200 bpm后，通过腔静脉闭塞改变压力。收缩末期压力-容积关系均呈线性（r = 0.97 ± 0.03，SD）。在心脏完好的犬中，Emax（收缩末期压力-容积关系的斜率）与每只犬的心率直接且单调相关，在峰值起搏速率时增加至对照组的238 +/-99%（p <0.05）。V0，该关系的零压截距也与每只犬的心率直接相关，从对照组到峰值起搏频率增加了8.6 +/-5.5 ml（p <0.05）。自主神经阻滞没有减弱这些影响。收缩末期压力-容积关系的这种快速变化导致每搏输出量从任何舒张末期容积减少，调节增强收缩性的血液动力学益处。心室舒张期间等容压下降的时间常数T由收缩末期压匹配的搏动确定。T与心率相关，在研究的心率范围内，在血管完整犬中下降20 +/-10.3%，在血管阻滞犬中下降23.1 +/-6.2%。因此，心室在更高的心率下更快地放松。我们的结论是，收缩频率的结论是一个重要的决定因素，在整个心动周期的整体泵功能在清醒的狗。
The effects of atrial pacing on the left ventricular end-systolic pressure-volume relation, a relatively load-insensitive index of left ventricular performance, were studied in 8 chronically instrumented, conscious dogs. Six of the dogs were studied while autonomically intact, and 2 were studied after autonomic blockade with 2 mg/kg i.v. propranolol and 0.2 mg/kg i.v. atropine. Left ventricular pressure was measured with a micromanometer and left ventricular volume was determined from 3 ultrasonic orthogonal dimensions. Pressure was varied by caval occlusions at control heart rate and after atrial pacing at 100, 120, 140, 160, 180, and 200 bpm. The end-systolic pressure-volume relation was linear in every case (r = 0.97 +/- 0.03, SD). In the autonomically intact dogs, Emax, the slope of the end-systolic pressure-volume relation, was directly and monotonically related to heart rate in every dog, increasing to 238 +/- 99% of control at peak pacing rate (p less than 0.05). V0, the zero pressure intercept of the relation was also directly related to heart rate in every dog and increased 8.6 +/- 5.5 ml from control to peak pacing rate (p less than 0.05). Autonomic blockade did not attenuate these effects. This rightward shift of the end-systolic pressure-volume relation results in a reduced stroke volume from any end-diastolic volume, modulating the hemodynamic benefits of enhanced contractility. T, the time constant of isovolumic pressure fall during ventricular relaxation, was determined from beats with matched end-systolic pressures. T was related to heart rate, falling by 20 +/- 10.3% over the range of rates studied in the autonomically intact dogs and by 23.1 +/- 6.2% in the autonomically blocked dogs. Thus, the ventricle relaxes more rapidly at higher heart rates. We conclude that the frequency of contraction is concluded as an important determinant of overall pump function throughout the cardiac cycle in conscious dogs.
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肝素从细胞表面释放硫酸乙酰肝素。
DOI：
--
发表时间：
1977
期刊：
Biochemical and Biophysical Research Communications - BBRC
影响因子：
--
作者：
P. Kraemer
通讯作者：
P. Kraemer
DOI：
10.1073/pnas.85.18.6992
发表时间：
1988-09-01
影响因子：
11.1
作者：
RATNER, N;HONG, D;GLASER, L
通讯作者：
GLASER, L
肝素结合内皮细胞生长因子的纯化和表征。
DOI：
--
发表时间：
1986
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Lobb,R;Sasse,J;Sullivan,R;Shing,Y;D'Amore,P;Jacobs,J;Klagsbrun,M
通讯作者：
Klagsbrun,M
DOI：
10.1073/pnas.82.18.6138
发表时间：
1985-01-01
影响因子：
11.1
作者：
SCHREIBER, AB;KENNEY, J;MACIAG, T
通讯作者：
MACIAG, T
从三七总皂甙和中枢神经系统中分离出的富含轴膜的组分对于培养的雪旺细胞具有促有丝分裂作用。
影响因子：
2.9
作者：
DeVries,GH;Salzer,JL;Bunge,RP
通讯作者：
Bunge,RP