Role of the peripheral chemoreceptor reflex on cardiovascular and sympathetic responses to obstructive sleep apnea in rats

Abstract

The potential contribution of peripheral chemoreceptors to the responses of systemic arterial pressure, heart rate, and sympathetic nerve activity (SNA) to obstructive sleep apnea was studied. Male Wistar rats had a tracheal balloon inserted to allow induction of apnea, with electrodes for measurement of renal SNA (RSNA) and lumbar SNA (LSNA), and a catheter for measurement of systemic arterial pressure. Electroencephalogram, electromyogram, and electrocardiogram records were also obtained. The tracheal balloon was inflated for 40 seconds during non‐rapid eye movement sleep. Systemic arterial pressure, RSNA, and LSNA increased after onset of tracheal balloon inflation while heart rate decreased. Bilateral carotid body section significantly attenuated the magnitude of the decrease in heart rate observed in intact rats, but had only minor effects on the responses of systemic arterial pressure, RSNA, and LSNA to obstructive sleep apnea. These data suggest that peripheral chemoreceptors may play a critical role in bradycardia in response to obstructive sleep apnea, and a minor role in the increases in systemic arterial pressure, RSNA, and LSNA in conscious rats. JSPS Grant.