| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Department of Physiology, Dartmouth Medical School, Lebanon, New Hampshire 03756; 2 School of Biomedical Engineering, Science and Health Systems, Drexel University, Philadelphia, Pennsylvania 19104; and 3 Department of Physiology, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom
This study evaluated possible neuronal mechanisms responsible for the transition from normal breathing (eupnea) to gasping. We hypothesized that a blockade of both inhibitory glycinergic synaptic transmission and potassium channels, combined with an increase in extracellular concentration of potassium, would induce a switch from an eupneic respiratory pattern to gasping. Efferent activities of the phrenic, vagal, and hypoglossal nerves were recorded during eupnea and ischemia-induced gasping in a perfused in situ preparation of the juvenile rat (4-6 wk of age). To block potassium channels, 4-aminopyridine (4-AP, 1-10 µM) was administered. Strychnine (0.2-0.6 µM) was used to block glycinergic neurotransmission. After administrations of 4-AP, excess extracellular potassium (10.25-17.25 mM), and strychnine, the incrementing pattern of eupneic phrenic activity was altered to a decrementing discharge. Hypoglossal and vagal activities became concentrated to the period of the phrenic burst with expiratory activity being reduced or eliminated. These changes in neural activities were similar to those in ischemia-induced gasping. Results are consistent with the concept that the elicitation of gasping represents a switch from a network-based rhythmogenesis for eupnea to a pacemaker-driven mechanism.
neural control of breathing; respiratory pattern generation; blockade of inhibition; ionic channels; hypoxia
This article has been cited by other articles:
|
|
 |
|
  K. L. Krause, H. V. Forster, T. Kiner, S. E. Davis, J. M. Bonis, B. Qian, and L. G. Pan Normal breathing pattern and arterial blood gases in awake and sleeping goats after near total destruction of the presumed pre-Botzinger complex and the surrounding region J Appl Physiol, February 1, 2009; 106(2): 605 - 619. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. A. Rybak, R. O'Connor, A. Ross, N. A. Shevtsova, S. C. Nuding, L. S. Segers, R. Shannon, T. E. Dick, W. L. Dunin-Barkowski, J. M. Orem, et al. Reconfiguration of the Pontomedullary Respiratory Network: A Computational Modeling Study With Coordinated In Vivo Experiments J Neurophysiol, October 1, 2008; 100(4): 1770 - 1799. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 V. Marchenko and R. F. Rogers Temperature and state dependence of dynamic phrenic oscillations in the decerebrate juvenile rat Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2007; 293(6): R2323 - R2335. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Johnson, L. M. Wiegel, and D. J. Majewski Are pacemaker properties required for respiratory rhythm generation in adult turtle brain stems in vitro? Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2007; 293(2): R901 - R910. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Marchenko and R. F. Rogers Time-frequency coherence analysis of phrenic and hypoglossal activity in the decerebrate rat during eupnea, hyperpnea, and gasping Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2006; 291(5): R1430 - R1442. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. B. Harris and W. M. St.-John Phasic pulmonary stretch receptor feedback modulates both eupnea and gasping in an in situ rat preparation Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2005; 289(2): R450 - R455. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. T. Potts, I. A. Rybak, and J. F. R. Paton Respiratory Rhythm Entrainment by Somatic Afferent Stimulation J. Neurosci., February 23, 2005; 25(8): 1965 - 1978. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. M. St.-John and J. C. Leiter High-frequency oscillations of phrenic activity in eupnea and gasping of in situ rat: influence of temperature Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2003; 285(2): R404 - R412. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. B. Harris and W. M. St.-John Tonic pulmonary stretch receptor feedback modulates both eupnea and gasping in an in situ rat preparation Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2003; 285(1): R215 - R221. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
I. C. Solomon, K. H. Chon, and M. N. Rodriguez Blockade of Brain Stem Gap Junctions Increases Phrenic Burst Frequency and Reduces Phrenic Burst Synchronization in Adult Rat J Neurophysiol, January 1, 2003; 89(1): 135 - 149. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
