Respiratory center
The respiratory center receives input from chemoreceptors, mechanoreceptors, the cerebral cortex, and the hypothalamus in order to regulate the rate and depth of breathing.Input is stimulated by altered levels of oxygen, carbon dioxide, and blood pH, by hormonal changes relating to stress and anxiety from the hypothalamus, and also by signals from the cerebral cortex to give a conscious control of respiration.[3] The dorsal respiratory group (DRG) has the most fundamental role in the control of respiration, initiating inspiration (inhalation).[4][5] The VRG maintains a constant breathing rhythm by stimulating the diaphragm and external intercostal muscles to contract, resulting in inspiration.[10] It limits the burst of action potentials in the phrenic nerve, effectively decreasing the tidal volume and regulating the respiratory rate.[11] When a faster rate of breathing is needed the pneumotaxic center signals the dorsal respiratory group to speed up.[12] In cats, after anaesthesia and vagotomy, pontine transaction has been described as evoking a long sustained inspiratory discharges interrupted by short expiratory pauses.[jargon] In rats on the other hand, after anaesthesia, vagotomy and pontine transaction, this breathing pattern was not observed, either in vivo or in vitro.These results suggest interspecies differences between rat and cat in the pontine influences on the medullary respiratory center.[13] The apneustic center of the lower pons appears to promote inhalation by constant stimulation of the neurons in the medulla oblongata.
Anatomical terminologymedulla oblongatabrainstemneuronshomeostaticchemoreceptorsmechanoreceptorscerebral cortexhypothalamusoxygencarbon dioxidehormonal changes relating to stressconscious controlmechanical ventilationcentral canalspinal cordrate of respirationnucleus of the solitary tractcranial nervesvagus nerveglossopharyngeal nerveperipheral chemoreceptorsbaroreceptorsstretch receptorsexhalationnucleus ambiguusinterneuronspre-Bötzinger complexpontine tegmentumsolitary nucleussubparabrachial nucleusmedial parabrachial nucleusantagonistaction potentialsphrenic nervetidal volumerespiratory raterhythmic bursts of activityvagotomyCentral pattern generatorautonomic nervous systemeupneadiaphragmexternal intercostal muscleselastic recoil of the lungsforceful exhalationShortness of breathbrain traumabrain damagebrain tumourischemiaopioidssedativesamphetamineControl of respirationCough centerGag reflexElsevierRespiratory physiologybreathinhalationobligate nasal breathingrespirometerpulmonary surfactantcomplianceelastic recoilhysteresivityairway resistancehyperresponsivenessconstrictiondilatationControlpneumotaxic centerapneustic centermedulladorsal respiratory groupventral respiratory groupcentralperipheralpulmonary stretch receptorHering–Breuer reflexLung volumesdead spacerespiratory minute volumeFEV1/FVC ratioLung function testsspirometrybody plethysmographypeak flow meternitrogen washoutpulmonary circulationhypoxic pulmonary vasoconstrictionpulmonary shuntventilation (V)PerfusionVentilation/perfusion ratioV/Q scanzones of the lunggas exchangepulmonary gas pressuresalveolar gas equationalveolar–arterial gradienthemoglobinoxygen–hemoglobin dissociation curveOxygen saturation2,3-BPGBohr effectHaldane effectcarbonic anhydrasechloride shiftoxyhemoglobinrespiratory quotientarterial blood gasdiffusion capacityhigh altitudedeath zoneoxygen toxicityhypoxiaGrey matterCranial nucleiGustatory nucleusVestibular nucleiLateralMedialInferiorHypoglossal nucleus