Effects of Swimming Training and Estrogen Terapy on C‐Type Natriuretic Peptide‐induced Relaxation in aorta of ovariectomized Hypertensive Rats

Abstract

Estrogen deficiency is detrimental to vascular function. On the other hand, the practice of exercise training and estrogen therapy improve vascular function. However, the effects of swimming training (SW) and estrogen therapy (ET) on the relaxation induced by C‐type natriuretic peptide (CNP) is unclear. Our aim was to investigate the effects of chronic SW and ET on CNP‐induced vascular relaxation in the aorta of ovariectomized hypertensive rats. The groups were randomly divided into sham (S), sham+SW (SSW), ovariectomized (OVX), ovariectomized+ET (OET), ovariectomized+SW (OSW) and ovariectomized+ET+SW (OET+SW). ET (5 mg of 17β‐Estradiol, s.c.) and SW (60 min – 5x/wk) were performed during eight weeks. Systolic blood pressure was measured before and after the training and treatment period. Aorta reactivity was performed in response to increased concentration of CNP. Ovariectomy significantly impairs the systolic blood pressure, while ET, SW and the association of both prevents this impairment. OVX reduces significantly the CNP‐induced vasorelaxation in the aorta of hypertensive animals. However, ET and SW were able to prevent the reduction caused by OVX, being able to maintain the relaxation at the same level as observed in sham animals. The association of ET and SW can also prevent the decrease in relaxation induced by CNP, but it did not show any additive effects. SW and ET prevent the ovariectomy‐induced worsening in vascular relaxation to CNP in hypertensive animals. Therefore, the practice of chronic exercise training can play a major role in the cardioprotection in hypertensive postmenopausal women.Support or Funding InformationUFES‐CApes‐CNPq‐Fapes