Recovery of peripheral chemoreceptor function after denervation in ponies

Area of Science:

• Cardiopulmonary physiology
• Neuroscience
• Respiratory regulation

Background:

• Peripheral chemoreceptors, primarily in the carotid bodies, are crucial for regulating ventilation.
• Surgical denervation of carotid bodies leads to significant alterations in respiratory control.

Purpose of the Study:

• To investigate the time-dependent recovery of peripheral chemoreceptor function after carotid body denervation in ponies.
• To determine the role of aortic chemoreceptors in maintaining ventilatory control post-surgery.

Main Methods:

• Surgical denervation of carotid sinus nerves and aortic arch adventitia in ponies.
• Assessment of resting ventilation (PaCO2) and ventilatory responses to hypoxia and NaCN over 4 years.
• Evaluation of chemoreceptor sensitivity in carotid and aortic areas under anesthesia.

Main Results:

• Immediate loss of peripheral chemoreceptor function and hypoventilation post-surgery.
• Partial, time-dependent recovery of chemoreceptor function between 2 and 22 months.
• Aortic chemoreceptors demonstrated functional recovery, compensating for carotid body denervation.

Conclusions:

• Aortic chemoreceptors play a significant role in ventilatory control in ponies following carotid body denervation.
• Peripheral chemoreceptor function recovers gradually, with aortic chemoreceptors becoming increasingly important.
• Ponies with denervated carotid bodies exhibit impaired acclimatization to chronic hypoxia.