Effect of local anaerobiosis on heart rate.
The isolated leg of a rat was connected to the body only by nerve and bone and was perfused with hypoxic Tyrode solution. Heart rate increased when metabolic parameters (PCO2, pH and lactate) reached values similar to those observed at the beginning of exercise. When the muscle was additionally stimulated by electric stimuli a significant temporal correlation between lactate and heart or respiratory rate was found. Metabolic changes caused by hypoxia and muscular contraction, in particular lactic acid, appear to act as chemical stimuli for metabolic muscle receptors participating in the generation of circulatory and respiratory responses to physical exercise.
Thimm
F
F
Physiologisches Institut, Universität Freiburg, F.R.G.
D000344:Afferent Pathways / Q000502:physiology; D000693:Anaerobiosis / Q000502:physiology; D000818:Animals; D006339:Heart Rate / Q000502:physiology*; D000860:Hypoxia / Q000503:physiopathology*; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology; D009119:Muscle Contraction / Q000502:physiology; D009132:Muscles / Q000294:innervation / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012119:Respiration / Q000502:physiology