<prompt> Sensitivity of chemoreceptors in COPDDecreased to HIncreased to HIncreased to PCO2Increased to PO2  <response>: The main chemoreceptors involved in respiratory feedback are: Central chemoreceptors: These are located on the ventrolateral surface of medulla oblongata and detect changes in the pH of spinal fluid. They can be desensitized over time from chronic hypoxia oxygen deficiency and increased carbon dioxide Ref: guyton and hall textbook of medical physiology 12 edition page number:365,366,367 