|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESPIRATORY |
1 Department of Physiology, Dartmouth Medical School, Lebanon, NH 03756-001, USA
Brainstem catecholamine (CA) neurones have wide projections and an arousal-state-dependent activity pattern. They are thought to modulate the processing of sensory information and also participate in the control of breathing. Mice with lethal genetic defects that include CA neurones have abnormal respiratory control at birth. Also the A6 region (locus coeruleus), which contains CA neurones sensitive to CO2in vitro, is one of many putative central chemoreceptor sites. We studied the role of CA neurones in the control of breathing during sleep and wakefulness by specifically lesioning them with antidopamine ß-hydroxylasesaporin (DBH-SAP) injected via the 4th ventricle. After 3 weeks there was a 7384% loss of A5, A6 and A7 tyrosine hydroxylase (TH) immunoreactive (ir) neurones along with 5660% loss of C1 and C2 phenyl ethanolamine-N-methyltransferase (PNMT)-ir neurones. Over the 3 weeks, breathing frequency decreased significantly during air and 3 or 7% CO2 breathing in both wakefulness and non-REM (NREM) sleep. The rats spent significantly less time awake and more time in NREM sleep. REM sleep time was unaffected. The ventilatory response to 7% CO2 was reduced significantly in wakefulness at 7, 14 and 21 days (28%) and in NREM sleep at 14 and 21 days (26%). Breathing variability increased in REM sleep but not in wakefulness or NREM sleep. We conclude that CA neurones (1) promote wakefulness, (2) participate in central respiratory chemoreception, (3) stimulate breathing frequency, and (4) minimize breathing variability in REM sleep.
(Received 26 September 2005;
accepted after revision 26 October 2005;
first published online 27 October 2005)
Corresponding author E. Nattie: Department of Physiology; Borwell Building, Dartmouth Medical School, Lebanon, NH, 03756-0001, USA. Email: eugene.nattie{at}dartmouth.edu
This article has been cited by other articles:
![]() |
B. Musizza, A. Stefanovska, P. V. E. McClintock, M. Palus, J. Petrovcic, S. Ribaric, and F. F. Bajrovic Interactions between cardiac, respiratory and EEG-{delta} oscillations in rats during anaesthesia J. Physiol., April 1, 2007; 580(1): 315 - 326. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Zhang and S. W. Mifflin Modulation of Synaptic Transmission to Second-Order Peripheral Chemoreceptor Neurons in Caudal Nucleus Tractus Solitarius by {alpha}1-Adrenoreceptors J. Pharmacol. Exp. Ther., February 1, 2007; 320(2): 670 - 677. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Zakynthinos, P. Katsaounou, M.-H. Karatza, C. Roussos, and T. Vassilakopoulos Antioxidants Increase the Ventilatory Response to Hyperoxic Hypercapnia Am. J. Respir. Crit. Care Med., January 1, 2007; 175(1): 62 - 68. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Nattie and A. Li Neurokinin-1 receptor-expressing neurons in the ventral medulla are essential for normal central and peripheral chemoreception in the conscious rat J Appl Physiol, December 1, 2006; 101(6): 1596 - 1606. [Abstract] [Full Text] [PDF] |
||||
![]() |
E. Chan, H. W. Steenland, H. Liu, and R. L. Horner Endogenous Excitatory Drive Modulating Respiratory Muscle Activity across Sleep-Wake States Am. J. Respir. Crit. Care Med., December 1, 2006; 174(11): 1264 - 1273. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Li, S. Zhou, and E. Nattie Simultaneous inhibition of caudal medullary raphe and retrotrapezoid nucleus decreases breathing and the CO2 response in conscious rats J. Physiol., November 15, 2006; 577(1): 307 - 318. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. Stornetta, T. S. Moreira, A. C. Takakura, B. J. Kang, D. A. Chang, G. H. West, J. F. Brunet, D. K. Mulkey, D. A. Bayliss, and P. G. Guyenet Expression of Phox2b by Brainstem Neurons Involved in Chemosensory Integration in the Adult Rat J. Neurosci., October 4, 2006; 26(40): 10305 - 10314. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. R. Noronha-de-Souza, K. C. Bicego, G. Michel, M. L. Glass, L. G. S. Branco, and L. H. Gargaglioni Locus coeruleus is a central chemoreceptive site in toads Am J Physiol Regulatory Integrative Comp Physiol, October 1, 2006; 291(4): R997 - R1006. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |