Which of the following factors does not alter the rate of breathing by influencing the chemoreceptors?

Central chemoreceptors are located in or near the medulla oblongata in the central nervous system. They respond to changes in H⁺ concentration or pCO₂, or both, in cerebrospinal fluid. Peripheral chemoreceptors are located in the aortic bodies and in the carotid bodies. The peripheral chemoreceptors are sensitive to changes in pO₂, H⁺, and pCO₂ in the arterial blood.