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Updated: Jun 7, 2026

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Published on: April 28, 2023
Intense exercise training induces adaptation in expression and responsiveness of cardiac β-adrenoceptors in diabetic
Solène Le Douairon Lahaye1, Arlette Gratas-Delamarche, Ludivine Malardé
1Laboratory Movement Sport and health Sciences, UFR APS, University of Rennes 2, Rennes, France. soleneledouairon@gmail.com
Background:
Informations about the effects of intense exercise training on diabetes-induced myocardial dysfunctions are lacking. We have examined the effects of intense exercise training on the cardiac function of diabetic rats, especially focusing on the Langendorff β-adrenergic responsiveness and on the β-adrenoceptors protein expression.
Methods:
Control or Streptozotocin induced-diabetic male Wistar rats were randomly assigned to sedentary or trained groups. The training program consisted of 8 weeks running on a treadmill (10° incline, up to 25 m/min, 60 min/day) and was considered to be intense for diabetic rats.
Results:
This intense exercise training amplified the in vivo diabetes-induced bradycardia. It had no effect on Langendorff basal cardiac contraction and relaxation performances in control and diabetic rats. In diabetic rats, it accentuated the Langendorff reduced responsiveness to β-adrenergic stimulation. It did not blunt the diabetes-induced decrease of β1-adrenoceptors protein expression, displayed a significant decrease in the β2-adrenoceptors protein expression and normalized the β3-adrenoceptors protein expression.
Conclusions:
Intense exercise training accentuated the decrease in the myocardial responsiveness to β-adrenergic stimulation induced by diabetes. This defect stems principally from the β2-adrenoceptors protein expression reduction. Thus, these results demonstrate that intense exercise training induces specific effects on the β-adrenergic system in diabetes.
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