Effect of adenosine receptor blockade with caffeine on sympathetic response to handgrip exercise in heart failure.
SourceAmerican Journal of Physiology : Heart and Circulatory Physiology, 281, 3, (2001), pp. H131-8
Article / Letter to editor
Display more detailsDisplay less details
American Journal of Physiology : Heart and Circulatory Physiology
SubjectEffects and kinetics of drugs in kidney and blood vessels; Effecten en lotgevallen van geneesmiddelen in nier en bloedvaten
Adenosine (Ado) increases muscle sympathetic nerve activity (MSNA) reflexively. Plasma Ado and MSNA are elevated in heart failure (HF). We tested the hypothesis that Ado receptor blockade by caffeine would attenuate reflex MSNA responses to handgrip (HG) and posthandgrip ischemia (PHGI) and that this action would be more prominent in HF subjects than in normal subjects. We studied 12 HF subjects and 10 age-matched normal subjects after either saline or caffeine (4 mg/kg) infusion during isometric [30% of maximal voluntary contraction (MVC)] and isotonic (10%, 30%, and 50%) HG exercise, followed by 2 min of PHGI. In normal subjects, caffeine did not block increases in MSNA during PHGI after 50% HG. In HF subjects, caffeine abolished MSNA responses to PHGI after both isometric and 50% isotonic exercise (P < 0.05) but MSNA responses during HG were unaffected. These findings are consistent with muscle metaboreflex stimulation by endogenous Ado during ischemic or intense nonischemic HG in HF and suggest an important sympathoexcitatory role for endogenous Ado during exercise in this condition.
Upload full text
Use your RU credentials (u/z-number and password) to log in with SURFconext to upload a file for processing by the repository team.