Not a fine wine: the ATP hypothesis may not get better with age.

摘要

The regulation of skeletal muscle blood flow during dynamic exercise involves the interaction of local metabolic and systemic neural signals which serve to match oxygen supply with demand. Sympathetic vaso-constriction is required during whole body dynamic exercise to assure maintenance of mean arterial pressure, given that skeletal muscle vasodilator capacity exceeds the potential of humans to increase cardiac output (Rowell et al. 1996). However, sympathetic vasoconstriction is limited in active muscle by local, presumably metabolic, factors in an intensity-dependent manner. This phenomenon was initially termed 'functional sympatholysis' but is now understood to encompass a blunting of vasoconstrictor transduction rather than an outright 'lysis' of sympathetic outflow to muscle (Hansen et al. 2000).