The Interaction Between Carotid Baroreceptor and Chemoreceptor Relexes on Cardiopulmonary Responses in Anaesthetized Cats

Hypertension and hypoxia often occur together in the clinical setting implying that the carotid baroreceptor and carotid chemoreceptors are affected simultaneously. This work was designed to study the effects of increased reflex sympathetic activity following carotid baroreceptor and chemoreceptor stimulation on reflex cardiopulmonary responses. The effects of unilateral carotid occlusion and chemoreceptor stimulation by intracarotid injection of sodium dithionite were studied singly and combined in 15 anaesthetized cats. Combined activation of the receptors resulted in responses that were generally more than the individual responses to activation of the receptors. We conclude that there is an interaction between the carotid baroreflex and chemoreflex but this, though synergistic is not additive. Nig. Qt. J. Hosp. Med. Vol.12(1-4) 2002: 6-