Regional Differences in Metabolism and Intracellular pH in Response to Moderate Hypoxia

It is well known that hypoxia induces increased respiration through activation of peripheral chemoreceptor reflex pathways. But, in the absence of afferent inputs from peripheral chemoreceptors, systemic hypoxia causes depression of breathing activity. Evidence of hypoxic depression of respiration also can be observed in animals and in humans with intact peripheral chemoreceptors.The effects of central hypoxia on respiratory activity require more time to develop than the effects of hypoxic stimulation through peripheral chemoreceptors, suggesting the involvement of relatively slow metabolic processes. The mechanism by which hypoxia causes central depression of breathing is not known, but several possibilites can be suggested.