HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Haller, M. Articles by Richter, D. W. Search for Related Content PubMed PubMed Citation Articles by Haller, M. Articles by Richter, D. W.

Dynamic activation of K_ATP channels in rhythmically active neurons

M. Haller, S. L. Mironov, A. Karschin * and D. W. Richter

1. The respiratory centre within the brainstem is one of the most active neuronal networks that generates ongoing rhythmic activity. Stabilization of such vital activity requires efficient processes for activity-correlated adjustment of neuronal excitability. Recent investigations have shown that a regulatory factor coupling electrical activity with cell metabolism comprises ATP-dependent K⁺ channels (K_ATP channels), which continuously adjust the excitability of respiratory neurons during normoxia and increasingly during hypoxia.
2. We used the single-cell antisense RNA amplification-polymerase chain reaction (PCR) technique to demonstrate that respiratory neurons co-express the sulphonylurea receptor SUR1 with the Kir6.2 potassium channel protein.
3. Single channel measurements on rhythmically active inspiratory neurons of the brainstem slice preparation of newborn mice revealed that K_ATP channels are periodically activated in synchrony with each respiratory cycle.
4. The Na⁺-K⁺-ATPase was inhibited with ouabain to demonstrate that oscillations of the channel open probability disappear, although respiratory activity persists for a longer time. Such findings indicate that K_ATP channel open probability reflects activity-dependent fluctuations in the ATP concentration within submembrane domains.
5. We also examined the effects of extracellular [K⁺] and hypoxia. All changes in the respiratory rhythm (i.e. changes in cycle length and burst durations) affected the periodic fluctuations of K_ATP channel activity.
6. The data indicate that K_ATP channels continuously modulate central respiratory neurons and contribute to periodic adjustment of neuronal excitability. Such dynamic adjustment of channel activity operates over a high range of metabolic demands, starting below physiological conditions and extending into pathological situations of energy depletion.

This article has been cited by other articles:

				S. L. Mironov Metabotropic glutamate receptors activate dendritic calcium waves and TRPM channels which drive rhythmic respiratory patterns in mice J. Physiol., May 1, 2008; 586(9): 2277 - 2291. [Abstract] [Full Text] [PDF]

				J. A. Hayes, J. L. Mendenhall, B. R. Brush, and C. A. Del Negro 4-Aminopyridine-sensitive outward currents in preBotzinger complex neurons influence respiratory rhythm generation in neonatal mice J. Physiol., April 1, 2008; 586(7): 1921 - 1936. [Abstract] [Full Text] [PDF]

				S. L. Mironov ADP Regulates Movements of Mitochondria in Neurons Biophys. J., April 15, 2007; 92(8): 2944 - 2952. [Abstract] [Full Text] [PDF]

				W. Ma, J. Berg, and G. Yellen Ketogenic Diet Metabolites Reduce Firing in Central Neurons by Opening KATP Channels J. Neurosci., April 4, 2007; 27(14): 3618 - 3625. [Abstract] [Full Text] [PDF]

				A. Nistri, K. Ostroumov, E. Sharifullina, and G. Taccola Tuning and playing a motor rhythm: how metabotropic glutamate receptors orchestrate generation of motor patterns in the mammalian central nervous system J. Physiol., April 15, 2006; 572(2): 323 - 334. [Abstract] [Full Text] [PDF]

				E. Sharifullina, K. Ostroumov, and A. Nistri Metabotropic glutamate receptor activity induces a novel oscillatory pattern in neonatal rat hypoglossal motoneurones J. Physiol., February 15, 2005; 563(1): 139 - 159. [Abstract] [Full Text] [PDF]

				K. Ballanyi Protective role of neuronal KATP channels in brain hypoxia J. Exp. Biol., August 15, 2004; 207(18): 3201 - 3212. [Abstract] [Full Text] [PDF]

				A. K. Tryba, F. Pena, and J.-M. Ramirez Stabilization of Bursting in Respiratory Pacemaker Neurons J. Neurosci., April 15, 2003; 23(8): 3538 - 3546. [Abstract] [Full Text] [PDF]