Adrenergic, Cholinergic, and Peripheral Chemoreceptor Effects on Thermal Panting in Cats

摘要: In several species ventilation not only serves acid-base homeostasis but also thermal homeostasis. Thermal panting is a quick and efficient way to dissipate heat. The central nervous system specially protected against disturbances, which are sensed immediately by the chemoreceptors, overheating because carotid blood cooled in rete mirabile before entering brain. almost invariably leads respiratory alkalosis. On other hand, alkalosis prerequisite for panting. Adding CO2 inspiratory air diminishes Apparently during heat stress, abandoned favor of thermostatic mechanisms (Richards 1970, Pleschka 1969) . functional pathways that mediate these conflicting interests thermoregulation control inputs from hypothalamus peripheral cheoreceptors, respectively, into neuronal organization. Schlaefke (1973) has shown when all chemo-afferents “respiratory centers” eliminated, stops. Only afferent activity able maintain rhythmic output electrical stimulation induces cats completely chemodenervated (See, 1976). We have cooling intermediate chemosensitive area at ventral medullary surface animals considerably enhances this panting, i.e., frequency increases tidal volume decreases. After chemodenervation we found no effect PA,CO 2level on (See et al., symp).