Arterial pressure responses to increasing interstitial potassium in hindlimb muscle of dogs.

K. J. Rybicki, Marc P Kaufman, J. L. Kenyon, J. H. Mitchell

Research output: Contribution to journalArticle

44 Scopus citations

Abstract

Static contraction of hindlimb skeletal muscle is known to increase reflexly arterial pressure and heart rate. Potassium is known to be released by the working muscle and is thought to activate the afferents responsible for the reflex cardiovascular responses to muscular contraction. However, it is not known whether potassium, at interstitial concentrations within the range observed during static contraction, is capable of stimulating these afferents. Thus we injected potassium into the gracilis artery of chloralose-anesthetized dogs while we measured interstitial potassium concentrations in the gracilis muscle with potassium-selective electrodes. In 16 dogs, we found that potassium injections, which increased interstitial potassium concentrations by 4.7 +/- 0.3 mM, increased mean arterial pressure by 18 +/- 3 mmHg and heart rate by 12 +/- 8 beats/min; cutting the obturator nerve abolished these increases. These heart rate and blood pressure responses were of short duration (20 +/- 7 s), even though interstitial potassium remained elevated for a period of several minutes. In 5 of the 16 dogs, static contraction of the gracilis muscle for 60 s increased interstitial potassium concentration by 4.3 +/- 0.3 mM. Our data are consistent with the hypothesis that potassium plays a role in causing the reflex cardiovascular responses to static muscular contraction.

Original languageEnglish (US)
JournalThe American journal of physiology
Volume247
Issue number4 Pt 2
StatePublished - Oct 1984
Externally publishedYes

ASJC Scopus subject areas

  • Medicine(all)

Fingerprint Dive into the research topics of 'Arterial pressure responses to increasing interstitial potassium in hindlimb muscle of dogs.'. Together they form a unique fingerprint.

  • Cite this