Neural mechanism of localized changes in skeletal muscle blood flow caused by moxibustion-like thermal stimulation of anesthetized rats.

Moxibustion-like thermal stimulation (MTS) was applied to the gastrocnemius muscle to measure local muscle blood flow (MBF) in the stimulated region and the change in the MBF in the region, and its mechanism was examined. In the experiment, we used urethane-anesthetized rats under artificial respiration and observed the change caused by gastrocnemius MTS using a laser Doppler blood-flow meter. MTS applied to the gastrocnemius muscle caused a two-phase response in blood flow that showed a transient decrease followed by an increase without blood pressure change. It is suggested that the increase in response occurs because of an axon reflex that has a reflex arc below the spinal cord, and the decrease in response is caused by direct stimulation of postganglionic muscle sympathetic fibers.