Muscle mechanoreflex mediates vasoconstriction in inactive limb in rats

• Main Authors: Masako Y Endo (Author), Naoyuki Hayashi (Author), Satoshi Koba (Author), Yuka Morizono (Author), Hatsumi Ueoka (Author), Chizuko Fujihara (Author), Yoshiyuki Fukuba (Author)
• Format: Book
• Published: Japanese Society of Physical Fitness and Sports Medicine, 2013-09-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 2186-8131; 2186-8123; 10.7600/jpfsm.2.381
• Keywords: vasoconstriction; mechanoreflex; sympathetic nerve; Sports medicine; RC1200-1245; Physiology; QP1-981
• Source: Journal of Physical Fitness and Sports Medicine, Vol 2, Iss 3, Pp 381-384 (2013)

We determined whether, stimulation of mechanosensitive receptors in active muscle (muscle mechanoreflex activation) induces vasoconstriction in the contralateral non-active muscles. In mid-collicular decerebrated rats (n = 9), we measured the blood flow of the left iliac artery when the right Achilles tendon was stretched by 300 g for 30 seconds (s) to stimulate mechanoreceptors in the triceps surae muscles. The stretch significantly increased the mean arterial pressure (MAP: +20 ± 3%, peak increase from baseline; mean ± SEM) and decreased the vascular conductance (VC) in the left iliac artery (-9 ± 1%, averaged over the stimulation period). After cutting the left sciatic nerve, the stretch did not significantly change the VC (+5 ± 1%), while it significantly increased MAP (+13 ± 3%, peak). In conclusion, the muscle mechanoreflex plays a role in mediating vasoconstriction in the contralateral limb via sympathetic activation.