HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 288/4/H1532    most recent 00673.2004v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (4) Citing Articles via Google Scholar Google Scholar Articles by Ichinose, M. Articles by Nishiyasu, T. Search for Related Content PubMed PubMed Citation Articles by Ichinose, M. Articles by Nishiyasu, T.

Muscle metaboreflex modulates the arterial baroreflex dynamic effects on peripheral vascular conductance in humans

Institute of Health and Sport Sciences, University of Tsukuba, Tsukuba City, Ibaraki, Japan

Submitted 7 July 2004 ; accepted in final form 23 November 2004

We aimed to investigate the interaction between the arterial baroreflex and muscle metaboreflex [as reflected by alterations in the dynamic responses shown by leg blood flow (LBF: by the ultrasound Doppler method), leg vascular conductance (LVC), mean arterial blood pressure (MAP), and heart rate (HR)] in humans. In 12 healthy subjects (10 men and 2 women), who performed sustained 1-min handgrip exercise at 50% maximal voluntary contraction followed immediately by an imposed postexercise muscle ischemia (PEMI), 5-s periods of neck pressure (NP; 50 mmHg) or neck suction (NS; –60 mmHg) were used to evaluate carotid baroreflex function both at rest (Con) and during PEMI. First, the decreases in LVC and LBF and the augmentation of MAP elicited by NP were all greater during PEMI than in Con (LVC, –1.2 ± 0.2 vs. –1.9 ± 0.2 ml·min^–1·mmHg^–1; LBF, –97.3 ± 11.2 vs. –177.0 ± 21.8 ml/min; MAP, 6.7 ± 1.2 vs. 11.5 ± 1.4 mmHg, Con vs. PEMI; each P < 0.05). Second, in Con, NS significantly increased both LVC and LBF (LVC, 0.9 ± 0.2 ml·min^–1·mmHg^–1; LBF, 46.6 ± 9.8 ml/min; significant change from baseline: each P < 0.05), and, whereas during PEMI no significant increases in LVC and LBF occurred during NS itself (LVC, 0.2 ± 0.1 ml·min^–1·mmHg^–1; LBF, 10.8 ± 9.6 ml/min; each P > 0.05), a decrease was evident in each parameters at 5 s after the cessation of NS. Third, during PEMI, the decrease in MAP elicited by NS was smaller (MAP, –8.4 ± 1.0 vs. –5.8 ± 0.4 mmHg, Con vs. PEMI; P < 0.05), and it recovered to its initial level more quickly after NS (vs. Con). Finally, however, the HR responses to NS and NP were not different between PEMI and Con. These results suggest that during muscle metaboreflex activation in humans, the arterial baroreflex dynamic effect on peripheral vascular conductance is modulated, as exemplified by 1) an augmentation of the NP-induced LVC decrease, and 2) a loss of the NS-induced LVC increase.

skeletal muscle metaboreflex; carotid baroreflex; exercise

This article has been cited by other articles:

				T. K. Pellinger and J. R. Halliwill Effect of propranolol on sympathetically mediated leg vasoconstriction in humans J. Physiol., September 1, 2007; 583(2): 797 - 809. [Abstract] [Full Text] [PDF]

				M. Ichinose, S. Koga, N. Fujii, N. Kondo, and T. Nishiyasu Modulation of the spontaneous beat-to-beat fluctuations in peripheral vascular resistance during activation of muscle metaboreflex Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H416 - H424. [Abstract] [Full Text] [PDF]

				T. Nishiyasu, M. Ichinose, W. G. Guntheroth, and H. L. Collins Comment on Point:Counterpoint "The muscle metaboreflex does/does not restore blood flow to contracting muscles" J Appl Physiol, February 1, 2006; 100(2): 750 - 751. [Full Text] [PDF]