Arterial chemoreceptors and sympathetic nerve activity: implications for hypertension and heart failure

HD Schultz, YL Li, Y Ding - Hypertension, 2007 - Am Heart Assoc
HD Schultz, YL Li, Y Ding
Hypertension, 2007Am Heart Assoc
hypoxemia, and as hypoxia ensues, the magnitudes of SNA and PNA increase
asymptotically and are maintained, whereas the ventilatory rate increases transiently and
then progressively declines. 13 When hypoxic stimulation is removed, PNA and SNA
gradually return to baseline rather than decrease abruptly (short-term potentiation). In
humans, a sustained period of hypoxemia for 20 minutes can elevate muscle SNA for as
long as 1 hour after blood gases and ventilation return to control. 17 After repeated episodes …
hypoxemia, and as hypoxia ensues, the magnitudes of SNA and PNA increase asymptotically and are maintained, whereas the ventilatory rate increases transiently and then progressively declines. 13 When hypoxic stimulation is removed, PNA and SNA gradually return to baseline rather than decrease abruptly (short-term potentiation). In humans, a sustained period of hypoxemia for 20 minutes can elevate muscle SNA for as long as 1 hour after blood gases and ventilation return to control. 17 After repeated episodes of short hypoxic exposures in rats (acute intermittent hypoxia), both PNA and SNA remain elevated for as long as 1 hour, a phenomenon called long-term facilitation. 18 The extent to which hypertension and CHF influence this complex and highly differentiated integration of sympathorespiratory responses to arterial chemoreflex activation is far from being fully realized. However, there is good evidence to indicate that the sensitivity of the arterial chemoreflex is enhanced in certain types of neurogenic hypertension and in CHF and that the enhanced CB function contributes to tonic elevation in sympathetic outflow to resistance vessels and kidney.
Am Heart Assoc