Effect of arterial occlusion on responses of group III and IV afferents to dynamic exercise

• Published in: Journal of applied physiology (1985) Vol. 84; no. 6; pp. 1827 - 1833
• Main Authors: Adreani, Christine M, Kaufman, Marc P
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Physiological Soc 01-06-1998; American Physiological Society
• Subjects: Animals; Arterial Occlusive Diseases - physiopathology; Biological and medical sciences; Blood; Blood vessels; Carbon Dioxide - blood; Cats; Electric Stimulation; Electromyography; Exercise; Fundamental and applied biological sciences. Psychology; Hindlimb - blood supply; Hindlimb - innervation; Hindlimb - physiology; Hydrogen-Ion Concentration; Motor control and motor pathways. Reflexes. Control centers of vegetative functions. Vestibular system and equilibration; Muscular system; Nervous system; Neurons, Afferent - physiology; Oxygen - blood; Physical Exertion - physiology; Regional Blood Flow - physiology; Vertebrates: nervous system and sense organs; Physical exercise; Fissipedia; Carnivora; Striated muscle; Muscle contraction; Motor control; Artery; Dynamic work; Vertebrata; Mammalia; Ischemia; Cat; Decerebration; Afferent projection; Sensory nerve
• ISSN: 8750-7587; 1522-1601
• DOI: 10.1152/jappl.1998.84.6.1827

Division of Cardiovascular Medicine, Departments of Internal
Medicine and Human Physiology, University of California, Davis,
California 95616
Our laboratory has shown
previously that a low level of dynamic exercise induced by electrical
stimulation of the mesencephalic locomotor region (MLR) stimulated
group III and IV muscle afferents in decerebrate unanesthetized cats
(C. M. Adreani, J. M. Hill, and M. P. Kaufman. J. Appl. Physiol. 83: 1811-1817, 1997). In the
present study, we have extended these findings by examining the effect
of occluding the arterial supply to the dynamically exercising muscles
on the afferents' responses to MLR stimulation. In decerebrate cats,
we found that arterial occlusion increased the responsiveness to a low
level of dynamic exercise in 44% of the group III and 47% of the
group IV afferents tested. Occlusion, compared with the freely perfused
state, did not increase the concentrations of either hydrogen ion or
lactate ion in the venous effluent from the exercising muscles. We
conclude that arterial occlusion caused some unspecified substance to
accumulate in the working muscles to increase the sensitivity of equal
percentages of group III and IV afferents to dynamic exercise.
muscular contraction; sensory nerves; decerebrate cats; ischemia