Sprint training improves postischemic, left ventricular diastolic performance.

نویسندگان

  • Joseph R Libonati
  • Zebulon V Kendrick
  • Steven R Houser
چکیده

We examined the effects of sprint training on left ventricular diastolic stiffness during normoxia and after ischemia-reperfusion (I/R). Thirty-seven, male Sprague-Dawley rats, weighing 150-175 g at the initiation of the experiment, were randomly assigned to a sedentary, control group (n = 20) or to a high-intensity, sprint-trained group (n = 17). Animals were trained 5 days/wk on a motor-driven treadmill for 6 wk. High-intensity sprint training consisted of running five 1-min sprints at 75 m/min, 15% grade, interspersed with 1-min active recovery runs at a speed of 20 m/min, 15% grade. Langendorff-derived isolated heart performance was measured before and after 20 min of no-flow ischemia followed by 30 min of reperfusion. Isolated myocytes were harvested from a subset of postischemic hearts. Sprint training reduced Langendorff-derived LV chamber stiffness (P < 0.05) and induced a rightward shift in the LV pressure-volume relationship during both normoxic perfusion and after I/R. LV developed pressure after I/R was also better preserved in hearts obtained from sprint-trained animals (P < 0.05), a result that is in part related to a lower postischemic LV chamber stiffness in sprint-trained hearts. The putative impact of sprint training on postischemic LV chamber stiffness was masked by glycolytic inhibition with iodoacetate, suggesting that glycolysis was involved in the better postischemic recovery observed in sprint-trained hearts. There was a tendency for enhanced postischemic cardiomyocyte shortening in sprint-trained cardiomyocytes compared with control. The rate of myocyte relaxation, i.e., time for 50% relaxation of the Ca(2+) transient amplitude, was similar between groups. These data suggest that additional mechanisms unrelated to Ca(2+) were involved in sprint-induced protection from ischemia-reperfusion-induced LV diastolic dysfunction.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

The effect of high-intensity interval training (HIIT) and quercetin supplementation on dimension and functional left ventricular adaptations in men with hypertension and CAD after PCI

Objective: The present study investigated the effects of 10-week High Intensity Interval Training (HIIT) and quercetin consumption on dimension and functional left ventricular adaptations in men with hypertension and coronary artery disease (CAD) after percutaneous coronary intervention (PCI).   Materials and Methods: In this semi-experimental randomized, placebo‑controlled and double‑blind s...

متن کامل

Effects of Addition of Sprint, Strength and Agility Training On Cardiovascular System in Young Male Field Hockey Players: An Echocardiography Based Study

To find training related physiological and cardiovascular changes and adaptations in field hockey players, this interventional study was conducted with 30 male field hockey trainees (age: 15.7±1.55 years, range: 13-20 years) undergoing training in preparation phase. In addition to the their usual routine of 2 hours per day, 6 times a week of aerobic, anaerobic and skill training session of fiel...

متن کامل

Na/H Exchange Inhibition With HOE642 Improves Postischemic Recovery due to Attenuation of Ca Overload and Prolonged Acidosis on Reperfusion

Background—Na/H exchange inhibition with HOE642 (cariporide) improves postischemic recovery of cardiac function, but the mechanisms of action remain speculative. Because Na/H exchange is activated on reperfusion, it was hypothesized that its inhibition delays realkalinization and decreases intracellular Na and, via Na/Ca exchange, Ca overload. Attenuated Ca overload and prolonged acidosis are k...

متن کامل

Na(+)/H(+) exchange inhibition with HOE642 improves postischemic recovery due to attenuation of Ca(2+) overload and prolonged acidosis on reperfusion.

BACKGROUND Na(+)/H(+) exchange inhibition with HOE642 (cariporide) improves postischemic recovery of cardiac function, but the mechanisms of action remain speculative. Because Na(+)/H(+) exchange is activated on reperfusion, it was hypothesized that its inhibition delays realkalinization and decreases intracellular Na(+) and, via Na(+)/Ca(2+) exchange, Ca(2+) overload. Attenuated Ca(2+) overloa...

متن کامل

Effects of brief repetitive ischemia on contractility, relaxation, and coronary flow. Exaggerated postischemic diastolic dysfunction in pressure-overload hypertrophy.

The recovery of systolic and diastolic function during unstable angina may be modified by the repetition of brief episodes of ischemia and by the presence of left ventricular hypertrophy (LVH). We studied the effects of six consecutive 5-minute cycles of no-flow ischemia and reperfusion followed by 25 minutes of recovery in isovolumic red blood cell-perfused hearts from aortic-banded rats with ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Journal of applied physiology

دوره 99 6  شماره 

صفحات  -

تاریخ انتشار 2005