BARORECEPTOR AND CHEMORECEPTOR CONTRIBUTIONS TO THE ASPHYXIA AND ASPHYXIA ALONG WITH NICOTINE (DRIP) INDUCED BLOOD PRESSURE AND URINE FLOW IN CONSCIOUS CAT

Abstract

Background: It has been evidenced in the literature that exposure to cigarette smoke causes cardio-renal changes. Baro- and chemo-receptors are the most important sensory receptors that participate in the maintenance of cardio-renal homeostasis. Any respiratory distress like asphyxia, emphysema and bronchitis also causes the same results. However, it has not been demonstrated how baro and chemoreflex functions are responsible for the alterations of cardio-renal homeostasis during cigarette smoking (nicotine) along with respiratory distress (asphyxia). Objective: The objective of the study was to evaluate the cardio-renal changes of cigarette smoking (nicotine exposure) along with respiratory distress (asphyxia) on baro- and chemo-reflex functions in cat. Methods: Experiments were carried out in 10 normal adult cats of either sex, weighing about 2 to 3 kg. Experimental asphyxia was induced by clamping the free end of the tracheal tube, through which the animal respired. Mean arterial blood pressure (MABP) and urine flow were evaluated through cannulation of the femoral artery and urethra during asphyxia (40 to 90 second) and nicotinic (20 μg/Kg. body weight/ min) condition. To observe the role of baro- and chemo-receptors, bilateral common carotid occlusion and sino-aortic denervation was made. Results: In case of both sino-aortic denervated and bilateral carotid artery occluded animals, asphyxia and asphyxia with ni cotine causes significantly increase of blood pressure (hypertension), which is modified by baro and chemoreceptors. Nicotine might excite the receptors further. Urine flow (antidiuresis and dieresis) is also modified partially at the same experimental condition but insignificant. Conclusions: Our data suggest that exposure to smoking (nicotine) along with respiratory distress (asphyxia) are enough to significantly aggravate the cardiovascular responses through baro and chemoreceptors sensitivity in cat. But renal parameter are partially modified through these receptors though it insignificant.