Improved myocardial efficiency in the working perfused heart of the spontaneously hypertensive rat.
Improved myocardial efficiency in the working perfused heart of the spontaneously hypertensive rat.
复制标题
提高自发性高血压大鼠工作灌注心脏的心肌效率。
作者：
J. Tubau;J. Wikman‐Coffelt;B. Massie;R. Sievers;W. Parmley
我们评估了心肌需氧量的决定因素——壁应力、峰值压力变化率和心率之间的关系，并测量了6个月大的自发性高血压大鼠（SHR）和对照Wistar-Kyoto大鼠（WKY）灌注后工作心脏在一系列负荷条件下的心肌耗氧量。采用两种离体心脏制剂，一种是主动脉射心制剂，一种是等容收缩制剂，分别添加和不添加异丙肾上腺素（10(-7)M）。在110 mm Hg恒定灌注压力下，两组心率、壁应力和压力峰值变化率无显著差异，但SHR组冠状动脉流量和心肌耗氧量明显降低。两种制剂的心肌高能磷酸化合物（5′-三磷酸腺苷、磷酸肌酸）和心肌乳酸的收缩值在SHR和WKY之间无显著差异。在最大发展压力（等容准备）下腺苷输注后，SHR和WKY均表现出冠状动脉储备的保存。这些结果表明，在6个月大的SHR中，心脏肥厚代表了一种代偿性适应，在最大压力下提高了机械效率，可能与在高血压动物中观察到的从V1到V2和V3异肌球蛋白表型的转变有关。
We assessed the relationship between determinants of myocardial oxygen demand--wall stress, peak rate of change of pressure and heart rate--and measured myocardial oxygen consumption over a range of loading conditions in the perfused, working heart of 6-month-old spontaneously hypertensive rats (SHR) and control Wistar-Kyoto rats (WKY). Two isolated heart preparations, an aortic-ejecting heart and an isovolumically contracting preparation with and without isoproterenol (10(-7)M) added, were employed. Under a constant perfusion pressure of 110 mm Hg, the heart rate, developed wall stress, and peak rate of change of pressure were not different between the two groups, but coronary flow and myocardial oxygen consumption were significantly lower in the SHR. Systolic values of myocardial high energy phosphate compounds (adenosine 5'-triphosphate, phosphocreatine) and myocardial lactate in the two preparations were not significantly different between SHR and WKY. Following adenosine infusion at maximum developed pressure (isovolumic preparation), both SHR and WKY demonstrated preservation of coronary reserve. These results indicate that cardiac hypertrophy represents a compensatory adaptation with improved mechanical efficiency in the 6-month-old SHR when maximally stressed and may be related to the shift from V1 to V2 and V3 isomyosin phenotypes that was observed in the hypertensive animals.
高血压大鼠心脏冠状动脉血流和心室功能受损。
影响因子：
10.8
作者：
Alfaro,A;Schaible,TF;Malhotra,A;Yipintsoi,T;Scheuer,J
通讯作者：
Scheuer,J
心率对左心室肥厚犬心肌血流量的影响。
DOI：
10.1152/ajpheart.1980.239.5.h621
发表时间：
1980
期刊：
The American journal of physiology
影响因子：
--
作者：
Vrobel,TR;Ring,WS;Anderson,RW;Emery,RW;Bache,RJ
通讯作者：
Bache,RJ