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) All Versions of this Article: 285/2/R404    most recent 00599.2002v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science 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 ISI Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by St.-John, W. M. Articles by Leiter, J. C. Search for Related Content PubMed PubMed Citation Articles by St.-John, W. M. Articles by Leiter, J. C.

CARDIAC, RENAL, AND RESPIRATORY INTEGRATION

High-frequency oscillations of phrenic activity in eupnea and gasping of in situ rat: influence of temperature

Department of Physiology, Dartmouth Medical School, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire 03756

Submitted 25 September 2002 ; accepted in final form 21 March 2003

We hypothesized that the in situ perfused preparation of the juvenile rat exhibits patterns of ventilatory activity comparable to eupnea and gasping in vivo. To evaluate this hypothesis, we examined high-frequency oscillations of activity of the phrenic nerve at 27–34°C. The peak frequency of these high-frequency oscillations was defined from power spectral analysis. In situ, recordings were obtained in hyperoxic normocapnia, during ventilatory cycles in which the peak of integrated phrenic activity was achieved late in the burst, as in eupnea in vivo. Recordings were also obtained in hypoxic hypercapnia, when the peak of integrated phrenic activity occurred in the first half of the burst, as in gasping in vivo. In situ, peak frequencies in the power spectra were significantly higher in gasping than during eupnea. Frequencies during eupnea and gasping were progressively elevated as the temperature of the in situ preparation was increased. The shift in peak frequencies between eupnea and gasping and the temperature sensitivity of frequencies in situ were the same as in vivo. Results provide additional support for the conclusion that the in situ preparation demonstrates distinctly different patterns of automatic ventilatory activity, comparable to eupnea and gasping in vivo.

in situ preparation; power spectra; peak frequency

This article has been cited by other articles:

				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]

				V. Marchenko and R. F. Rogers Selective loss of high-frequency oscillations in phrenic and hypoglossal activity in the decerebrate rat during gasping Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2006; 291(5): R1414 - R1429. [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]

				W. M St.-John, J. F. R Paton, and J. C Leiter Uncoupling of rhythmic hypoglossal from phrenic activity in the rat Exp Physiol, November 1, 2004; 89(6): 727 - 737. [Abstract] [Full Text] [PDF]