Univ. of Pennsylvania School of Nursing, Biobehavioral and Health Sciences, Philadelphia, PA, USA.
J Appl Physiol (1985). 2011 Dec;111(6):1637-43. doi: 10.1152/japplphysiol.00292.2011. Epub 2011 Sep 15.
The general purpose of this study was to test the effect of exercise training on the left ventricular (LV) pressure-volume relationship (LV/PV) and apoptotic signaling markers in normotensive and hypertensive hearts. Four-month-old female normotensive Wistar-Kyoto rats (WKY; n = 37) and spontaneously hypertensive rats (SHR; n = 38) were assigned to a sedentary (WKY-SED, n = 21; SHR-SED, n = 19) or treadmill-trained (WKY-TRD, n = 16; SHR-TRD, n = 19) group (∼60% Vo(2 peak), 60 min/day, 5 days/wk, 12 wk). Ex vivo LV/PV were established in isovolumic Langendorff-perfused hearts, and LV levels of Akt, phosphorylated Akt (Akt(Pi)), Bad, phosphorylated Bad (Bad(Pi)) c-IAP, x-IAP, calcineurin, and caspases 3, 8, and 9 were measured. Heart-to-body weight ratio was increased in SHR vs. WKY (P < 0.05), concomitant with increased calcineurin mRNA (P < 0.05). There was a rightward shift in the LV/PV (P < 0.05) and a reduction in systolic elastance (E(s)) in SHR vs. WKY. Exercise training corrected E(s) in SHR (P < 0.05) but had no effect on the LV/PV in WKY. Caspase 3 was increased in SHR-SED relative to WKY-SED, while Bad(Pi,) c-IAP, and x-IAP were significantly lower in SHR relative to WKY (P < 0.05). Exercise training increased Bad(Pi) in both WKY and SHR but did not alter caspase 9 activity in either group. While caspase 3 activity was increased with training in WKY (P < 0.05), it was unchanged with training in SHR. We conclude that moderate levels of regular aerobic exercise attenuate systolic dysfunction early in the compensatory phase of hypertrophy, and that a differential phenotypical response to moderate-intensity exercise exists between WKY and SHR.
本研究的主要目的是检验运动训练对正常血压和高血压心脏的左心室（LV）压力-容积关系（LV/PV）和凋亡信号标志物的影响。将 4 月龄雌性正常血压 Wistar-Kyoto 大鼠（WKY；n=37）和自发性高血压大鼠（SHR；n=38）分为安静组（WKY-SED，n=21；SHR-SED，n=19）和跑台训练组（WKY-TRD，n=16；SHR-TRD，n=19）（约 60% Vo(2 peak)，60 min/d，5 d/wk，12 wk）。通过在离体 Langendorff 灌注心脏中建立 LV/PV，测量 LV 中 Akt、磷酸化 Akt（Akt(Pi)）、Bad、磷酸化 Bad（Bad(Pi)）、c-IAP、x-IAP、钙调神经磷酸酶和半胱天冬酶 3、8 和 9 的水平。与 WKY 相比，SHR 的心脏/体重比增加（P<0.05），同时钙调神经磷酸酶 mRNA 增加（P<0.05）。与 WKY 相比，SHR 的 LV/PV 出现右移（P<0.05），收缩弹性（E(s)）降低。运动训练校正了 SHR 的 E(s)（P<0.05），但对 WKY 的 LV/PV 没有影响。与 WKY-SED 相比，SHR-SED 中的半胱天冬酶 3 增加，而 Bad(Pi)、c-IAP 和 x-IAP 则明显低于 WKY（P<0.05）。运动训练增加了 WKY 和 SHR 中的 Bad(Pi)，但两组的半胱天冬酶 9 活性都没有改变。虽然 WKY 中的半胱天冬酶 3 活性随训练而增加（P<0.05），但 SHR 中的半胱天冬酶 3 活性不变。我们的结论是，中等强度的规律有氧运动可减轻代偿性心肌肥厚早期的收缩功能障碍，WKY 和 SHR 对中等强度运动的表型反应存在差异。
