Botzinger complex
In mammals, the Bötzinger complex (BötC) is a group of neurons located in the rostral ventrolateral medulla, and ventral respiratory column. In the medulla, this group is located caudally to the facial nucleus and ventral to nucleus ambiguus.[1][2]
Function
The Bötzinger complex plays an important role in controlling breathing[3][4] and responding to hypoxia.[5][6] The Bötzinger complex consists primarily of glycinergic neurons[7] which inhibit respiratory activity. Of the respiratory cycle phases BötC generates post-inspiratory (Post-I) activity and augmenting expiratory (aug-e) activity.[8][9][10]
Name
The Bötzinger complex was named by UCLA Professor Jack Feldman in 1978, after a bottle of white wine named Botzinger present at his table during a scientific meeting in Hirschhorn, Germany, that year.
Connections
The Bötzinger Complex has projections to
- Phrenic pre-motor neurons in the medulla[11]
- Phrenic motor neurons in the cervical spinal cord[12][13]
- The dorsal respiratory group (DRG) [12][14]
- Ventral respiratory group (VRG)[11][12][15]
- Pre-Bötzinger complex[16]
- Bötzinger complex [2][12][17][18]
- Parabrachial Kolliker-Fuse nucleus[19]
Only augmenting expiratory neurons of BötC, which are exclusively glycinergic, project to the phrenic nucleus.[20][13]
Projections to the Bötzinger complex include the nucleus tractus solitarii (NTS)[21][22] the DRG and the VRG.[23]
Physiology
These neurons are intrinsic pacemakers.[24] Post-I neurons display an initial burst of activity followed by decrease in activity at the end of inspiration. Aug-E neurons begin firing during the E2 phase and end before the phrenic nerve burst.[18][25]
References
- Bianchi AL, Grélot L, Iscoe S, Remmers JE (1988). "Electrophysiological properties of rostral medullary respiratory neurones in the cat: an intracellular study". J Physiol. 407: 293–310. doi:10.1113/jphysiol.1988.sp017416. PMC 1191204. PMID 3256618.
- Otake K, Sasaki H, Mannen H, Ezure K (1987). "Morphology of expiratory neurons of the Bötzinger complex: an HRP study in the cat". J Comp Neurol. 258 (4): 565–79. doi:10.1002/cne.902580407. PMID 3034989.
- Bongianni F, Corda M, Fontana GA, Pantaleo T (1991). "Reciprocal connections between rostral ventrolateral medulla and inspiration-related medullary areas in the cat". Brain Res. 565 (1): 171–4. doi:10.1016/0006-8993(91)91751-l. PMID 1773353.
- Guyenet PG (2000). "Neural structures that mediate sympathoexcitation during hypoxia". Respir Physiol. 121 (2–3): 147–62. doi:10.1016/s0034-5687(00)00125-0. PMID 10963771.
- Hirooka Y, Polson JW, Potts PD, Dampney RA (1997). "Hypoxia-induced Fos expression in neurons projecting to the pressor region in the rostral ventrolateral medulla". Neuroscience. 80 (4): 1209–24. doi:10.1016/s0306-4522(97)00111-5. PMID 9284071.
- Nitsos I, Walker DW (1999). "The distribution of FOS-immunoreactive neurons in the brainstem, midbrain and diencephalon of fetal sheep in response to acute hypoxia in mid and late gestation". Brain Res Dev Brain Res. 114 (1): 9–26. doi:10.1016/s0165-3806(99)00010-3. PMID 10209238.
- Winter SM, Fresemann J, Schnell C, Oku Y, Hirrlinger J, Hülsmann S (2009). "Glycinergic interneurons are functionally integrated into the inspiratory network of mouse medullary slices". Pflügers Arch. 458 (3): 459–69. doi:10.1007/s00424-009-0647-1. PMC 2691554. PMID 19238427.
- Richter A, Heyne K, Sagebiel J, Weber M (1986). "[Respiratory emergency in the newborn infant: extreme laryngotracheo-esophageal cleft (esophagotrachea)]". Monatsschr Kinderheilkd. 134 (12): 874–7. PMID 3821744.
- Richter DW (1982). "Generation and maintenance of the respiratory rhythm". J Exp Biol. 100: 93–107. PMID 6757372.
- Merrill EG (1981). "Where are the real respiratory neurons?". Fed Proc. 40 (9): 2389–94. PMID 7250385.
- Jiang C, Lipski J (1990). "Extensive monosynaptic inhibition of ventral respiratory group neurons by augmenting neurons in the Bötzinger complex in the cat". Exp Brain Res. 81 (3): 639–48. doi:10.1007/bf02423514. PMID 2226695.
- Otake K, Sasaki H, Ezure K, Manabe M (1988). "Axonal projections from Bötzinger expiratory neurons to contralateral ventral and dorsal respiratory groups in the cat". Exp Brain Res. 72 (1): 167–77. doi:10.1007/bf00248512. PMID 3169184.
- Tian GF, Peever JH, Duffin J (1998). "Bötzinger-complex expiratory neurons monosynaptically inhibit phrenic motoneurons in the decerebrate rat". Exp Brain Res. 122 (2): 149–56. doi:10.1007/s002210050502. PMID 9776513.
- Lipski J, Merrill EG (1980). "Electrophysiological demonstration of the projection from expiratory neurones in rostral medulla to contralateral dorsal respiratory group". Brain Res. 197 (2): 521–4. doi:10.1016/0006-8993(80)91140-3. PMID 7407571.
- Bryant TH, Yoshida S, de Castro D, Lipski J (1993). "Expiratory neurons of the Bötzinger Complex in the rat: a morphological study following intracellular labeling with biocytin". J Comp Neurol. 335 (2): 267–82. doi:10.1002/cne.903350210. PMID 8227518.
- Richter DW, Smith JC (2014). "Respiratory rhythm generation in vivo". Physiology. 29 (1): 58–71. doi:10.1152/physiol.00035.2013. PMC 3929116. PMID 24382872.
- Shen L, Li YM, Duffin J (2003). "Inhibitory connections among rostral medullary expiratory neurones detected with cross-correlation in the decerebrate rat". Pflügers Arch. 446 (3): 365–72. doi:10.1007/s00424-003-1024-0. PMID 12687375.
- Smith JC, Abdala AP, Koizumi H, Rybak IA, Paton JF (2007). "Spatial and functional architecture of the mammalian brain stem respiratory network: a hierarchy of three oscillatory mechanisms". J Neurophysiol. 98 (6): 3370–87. doi:10.1152/jn.00985.2007. PMC 2225347. PMID 17913982.
- Ezure K, Tanaka I, Saito Y (2003). "Brainstem and spinal projections of augmenting expiratory neurons in the rat". Neurosci Res. 45 (1): 41–51. doi:10.1016/s0168-0102(02)00197-9. PMID 12507723.
- Schreihofer AM, Stornetta RL, Guyenet PG (1999). "Evidence for glycinergic respiratory neurons: Bötzinger neurons express mRNA for glycinergic transporter 2". J Comp Neurol. 407 (4): 583–97. doi:10.1002/(sici)1096-9861(19990517)407:4<583::aid-cne8>3.0.co;2-e. PMID 10235646.
- Accorsi-Mendonça D, Bonagamba LG, Leão RM, Machado BH (2009). "Are L-glutamate and ATP cotransmitters of the peripheral chemoreflex in the rat nucleus tractus solitarius?". Exp Physiol. 94 (1): 38–45. doi:10.1113/expphysiol.2008.043653. PMID 18931046.
- Ruff F, Caubarrere I, Salem A, Dubois F, Duroux P (1975). "[Regional distribution of pulmonary perfusion during fluid overload in man]". Ann Anesthesiol Fr. 16 Spec No 2-3: 164–8. PMID 9861.
- Douse MA, Duffin J (1992). "Projections to Bötzinger expiratory neurons by dorsal and ventral respiratory group neurons". NeuroReport. 3 (5): 393–6. doi:10.1097/00001756-199205000-00004. PMID 1633274.
- Almado CE, Leão RM, Machado BH (2014). "Intrinsic properties of rostral ventrolateral medulla presympathetic and bulbospinal respiratory neurons of juvenile rats are not affected by chronic intermittent hypoxia". Exp Physiol. 99 (7): 937–50. doi:10.1113/expphysiol.2013.077800. PMID 24728679.
- Moraes DJ, Bonagamba LG, Costa KM, Costa-Silva JH, Zoccal DB, Machado BH (2014). "Short-term sustained hypoxia induces changes in the coupling of sympathetic and respiratory activities in rats". J Physiol. 592 (Pt 9): 2013–33. doi:10.1113/jphysiol.2013.262212. PMC 4230776. PMID 24614747.