Sensory Stimulation (Electro-Acupuncture) and Physical Exercise, Effects on Blood Pressure, and Nociception

Abstract
The effects of treatment with sensory stimulation (electroacupuncture) or physical exercise (running) on heart rate, blood pressure and nociceptive thresholds in spontaneously hypertensive rats were studied. Both electroacupuncture and running increased blood pressure and heart rate when measured immediately after the experiment. Two hours later and at 8 and 16 h the heart rate values did not differ from the controls, while blood pressure was significantly decreased but returned to control level 16 h later. The experimental procedure significantly increased the nociceptive threshold which remained higher two hours later but did not differ from the controls after 8 and 16 hours. Concentrations of neuropeptide Y and calcitonin gene-related peptide in cerebrospinal fluid, plasma and muscle perfusate were measured immediately and 2, 8 and 16 h after the treatment. Increased levels of calcitonin gene-related peptide-like immunoreactivity and biphasical changes of neuropeptide Y-like immunoreactivity were found in all tissues analysed after electroacupuncture and running. The finding of similar changes in neuropeptides, blood pressure and nociception following electroacupuncture and running gives support to the hypothesis that sensory stimulation may stimulate endogenous control systems similarly as physical exercise.