The pneumotaxic center, also known as the pontine respiratory group (PRG), is a network of neurons in the rostral dorsal lateral pons. It consists of the Kölliker-Fuse nucleus and the medial parabrachial nucleus. It is considered an antagonist to the apneustic center, which produces abnormal breathing during inhalation. It limits inspiration.
The PRG antagonizes the apneustic center, cyclically inhibiting inhalation. The PRG limits the burst of action potentials in the phrenic nerve, effectively decreasing the tidal volume and regulating the respiratory rate. Absence of the PRG results in an increase in depth of respiration and a decrease in respiratory rate.
The PRG regulates the amount of air a person can take into the body in each breath. The dorsal respiratory group has rhythmic bursts of activity that are constant in duration and interval. When we need to breathe faster, the PRG tells the dorsal respiratory group to speed up. When we need longer breaths the bursts of activity are elongated. All the information that our body uses to help us breath happens in the pneumotaxic center. If this was damaged or in any way harmed it would make breathing on our own almost impossible. One study on this subject was on anesthetized paralyzed cats before and after bivagotomy. Ventilation was monitored in awake and anesthetized cats breathing air or CO2. Ventilation was monitored both before and after lesions to the pneumotaxic center region and after subsequent bilateral vagotomy. Cats with pontine lesions had a prolonged inhalation duration. In cats, after anaesthesia and bivagotomy, pontine transection has been described as evoking a long sustained inspiratory discharges interrupted by short expiratory pauses. In rats on the other hand, after anaesthesia, bivagotomy and pontine transection, 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 generator.
- Song, Gang; Yu, Yunguo; Poon, Chi-Sang (2006). "Cytoarchitecture of Pneumotaxic Integration of Respiratory and Nonrespiratory Information in the Rat". Journal of Neuroscience. 26 (1): 300–10. doi:10.1523/JNEUROSCI.3029-05.2006. PMID 16399700.
- Dutschmann, Mathias; Dick, Thomas E. (2012). "Comprehensive Physiology". doi:10.1002/cphy.c100015. ISBN 978-0-470-65071-4.
- Gautier, H; Bertrand, F (1975). "Respiratory effects of pneumotaxic center lesions and subsequent vagotomy in chronic cats". Respiration Physiology. 23 (1): 71–85. doi:10.1016/0034-5687(75)90073-0. PMID 1129551.
- Monteau, R.; Errchidi, S.; Gauthier, P.; Hilaire, G.; Rega, P. (1989). "Pneumotaxic centre and apneustic breathing: Interspecies differences between rat and cat". Neuroscience Letters. 99 (3): 311–6. doi:10.1016/0304-3940(89)90465-5. PMID 2725956.
- Levitzky, Michael G. (2002). Pulmonary Physiology (6th ed.). McGraw-Hill Professional. pp. 193–4. ISBN 0-07-138765-X.
- Costanzo, Linda S. (2006). Physiology (3rd ed.). Philadelphia, PA: Elsevier. p. 224. ISBN 978-1-4160-2320-3.
- Shannon, Roger; Baekey, David M.; Morris, Kendall F.; Nuding, Sarah C.; Segers, Lauren S.; Lindsey, Bruce G. (2004). "Pontine respiratory group neuron discharge is altered during fictive cough in the decerebrate cat". Respiratory Physiology & Neurobiology. 142 (1): 43–54. doi:10.1016/j.resp.2004.05.002. PMID 15351303.