How do peripheral chemoreceptors affect ventilation in comparison to central chemoreceptors?

How do peripheral chemoreceptors affect ventilation in comparison to central chemoreceptors?

• A. Immediately, immediate
• B. Immediately, delayed
• C. Delayed, immediate
• D. Delayed, delayed

Answer: (B)

Peripheral chemoreceptors, located mainly in the carotid and aortic bodies, respond rapidly to changes in the arterial partial pressures of oxygen (PaO2), carbon dioxide (PaCO2), and pH. When oxygen levels drop or carbon dioxide levels rise, these receptors stimulate ventilation to quickly restore homeostasis. This immediate response helps maintain adequate oxygenation and carbon dioxide elimination during acute respiratory challenges. Central chemoreceptors, found in the medulla oblongata, primarily respond to changes in carbon dioxide levels and pH in the cerebrospinal fluid. Their response, although also regulatory for ventilation, is slower compared to peripheral chemoreceptors. This delay is due to the time required for CO2 to diffuse across the blood-brain barrier and affect the central chemoreceptors, providing a more gradual adjustment to ventilation rates. Thus, the correct interpretation highlights that peripheral chemoreceptors act immediately in response to acute changes, while central chemoreceptors have a delayed effect as they adapt the ventilation based on CO2 or pH changes over a longer timeframe.

Peripheral chemoreceptors, located mainly in the carotid and aortic bodies, respond rapidly to changes in the arterial partial pressures of oxygen (PaO2), carbon dioxide (PaCO2), and pH. When oxygen levels drop or carbon dioxide levels rise, these receptors stimulate ventilation to quickly restore homeostasis. This immediate response helps maintain adequate oxygenation and carbon dioxide elimination during acute respiratory challenges.

Central chemoreceptors, found in the medulla oblongata, primarily respond to changes in carbon dioxide levels and pH in the cerebrospinal fluid. Their response, although also regulatory for ventilation, is slower compared to peripheral chemoreceptors. This delay is due to the time required for CO2 to diffuse across the blood-brain barrier and affect the central chemoreceptors, providing a more gradual adjustment to ventilation rates.

Thus, the correct interpretation highlights that peripheral chemoreceptors act immediately in response to acute changes, while central chemoreceptors have a delayed effect as they adapt the ventilation based on CO2 or pH changes over a longer timeframe.