Peripheral chemoreceptors responds to hyproxia by oxygen sensitive:: (A) Na+ channel, (B) Ca+2 channel, (C) K+ channel, (D) CI- channel
Answer is C. O2 levels are regulated almost entirely by peripheral chemoreceptors located in the carotid and aoic bodies; which in turn transmit appropriate signals to the respiratory center in the brain Carotid & aoic bodies have GLOMUS CELLS (multiple highly characteristic glandular - like cells) that synapse directly with nerve endings. Glomus cells have O2 sensitive K+ channels that are inactivated when blood Po2 decrease markedly. HYPOXIA O2 sensitive K+ channels inactivated. | Glomus cell depolarizes | Voltage gated Ca++ channel open, increase intracellular Ca++ | Neurotransmitter released, activates afferent neurons to CNS center of respiration.