1. Chemical Control of Respiration
Central Chemoreceptors
Peripheral Chemoreceptors

2. Stimulation of inspiratory area by the signals from the chemosensitive area

3. Location of the peripheral Chemoreceptors

4. Effect of Increased arterial Pco2 on ventilation
Brain ECF Pco2
(When
arterial CO2 + H2O
Pco2 Brain ECF
>70 – H2CO3
mm Hg)
H + HCO3
Brain ECF H
Weakly+
Medullary
Peripheral Respiratory Central
Chemoreceptors Center Chemoreceptors
Ventilation
Arterial PCO2 ( ) Ca + + +

5. Peripheral Chemoreceptors
Situated in aortic and carotid bodies
Respond to
Decreases in arterial PO2
Increases in arterial PCO2
Decreases in arterial pH

6. Effect of threateningly low arterial Po2 on ventilation
Arterial Po2 < 60 mm Hg
Emergency
Life-Saving
mechanism
Peripheral Medullary Central
Chemoreceptors Respiratory Chemoreceptors
Center
Ventilation
Arterial Po2
Relieves + - - No
effect on +