Kuznetsov V I, Pruss G M
Kosm Biol Aviakosm Med. 1987 Mar-Apr;21(2):55-8.
Adaptation of the heart of hypokinetic rats to sustained afterload and the role of nervous regulation in this process were investigated. The experimental rats were subdivided into four groups: 1) control, 2) hypokinesia for 64 days, 3) coarctation of aorta for 4 days, and 4) hypokinesia for 60 days plus coarctation of aorta for 4 days. It was found that the rates of contraction and relaxation of the heart increased by 22 = 51% in the Group 2 rats and decreased by 32 = 40% in the Group 3 rats as compared to the controls. Coarctation of aorta that followed 60-day hypokinesia (Group 4) reduced the increased parameters to the control level. After heart denervation (vagotomy and drug desympathization) all the rats showed depression of the contractile parameters to a varying degree: Group 2 rats exhibited the lowest degree of depression. It can be concluded that cardiac resistance of the hypokinetic rats to afterload is higher than in the intact rats with coarctation of aorta; on the other hand, afterload reduces the hypokinesia-induced increase in the contractility function, making it close to the control level. In addition to the nervous influences (sympathetic), intracardiac factors play an important role in the mechanisms of adaptation of the heart to hypokinesia and of the hypokinetic heart to afterload.
研究了运动功能减退大鼠心脏对持续后负荷的适应情况以及神经调节在此过程中的作用。将实验大鼠分为四组：1）对照组；2）运动功能减退64天组；3）主动脉缩窄4天组；4）运动功能减退60天加主动脉缩窄4天组。结果发现，与对照组相比，第2组大鼠心脏的收缩和舒张速率增加了22% = 51%，第3组大鼠的收缩和舒张速率降低了32% = 40%。60天运动功能减退后进行主动脉缩窄（第4组）使增加的参数降至对照水平。心脏去神经支配（迷走神经切断术和药物性去交感神经）后，所有大鼠的收缩参数均有不同程度的降低：第2组大鼠的降低程度最低。可以得出结论，运动功能减退大鼠心脏对后负荷的耐受性高于完整的主动脉缩窄大鼠；另一方面，后负荷可降低运动功能减退引起的收缩功能增加，使其接近对照水平。除了神经影响（交感神经）外，心脏内因素在心脏适应运动功能减退以及运动功能减退心脏适应后负荷的机制中起重要作用。
