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: 91/4/755    most recent expphysiol.2006.033274v1 Alert me when this article is cited Alert me if a correction is posted 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 Google Scholar Google Scholar Articles by Pedersen, B. L. Articles by Quistorff, B. Search for Related Content PubMed PubMed Citation Articles by Pedersen, B. L. Articles by Quistorff, B. Related Collections Muscle

¹ Nuclear Magnetic Resonance Centre, Department of Medical Biochemistry and Genetics, The Panum Institute² Department of Thoracic Surgery³ Department of Anaesthesia, Rigshospitalet, University of Copenhagen, Denmark

This study presents a perfused preparation for evaluation of metabolism in pig intercostal muscle in vitro. Preserved vessels and nerves to an intercostal segment including two adjacent ribs allowed for tissue perfusion and electrical stimulation with measurement of contraction force, oxygen consumption and ³¹P-magnetic resonance spectroscopy (³¹P-MRS). When perfused at rest with Krebs–Ringer buffer, the preparation maintained physiological levels of phosphocreatine (PCr), inorganic phosphate (P_i), ATP and pH at a stable oxygen consumption of 0.51 ± 0.01 µmol min^–1 g^–1 for more than 2 h. Tonic stimulation of the nerve caused anaerobic energy consumption as PCr and pH decreased, and both variables recovered after the contraction with half-time values of 7 min. Force increased to 0.040 N g^–1 (range, 0.031–0.103 N g^–1) and it gradually decreased by about 70% during the subsequent 5 min of stimulation. The calculated free ADP concentration increased from 7.4 ± 2.1 nmol g^–1 at rest to 28 ± 12 nmol g^–1 (mean ± S.D.) by the end of the stimulation. Thus anaerobic ATP turnover was zero at rest, 6.1 ± 2 µmol min^–1 g^–1 during the first minute of stimulation and 3.5 ± 0.5 µmol min^–1 g^–1 during the two last minutes, corresponding to the drop in force. When the preparation was left unperfused, anaerobic ATP turnover averaged 0.40 ± 0.15 µmol min^–1 g^–1 for the first 10 min. The preparation can also be applied to human intercostal muscles, as demonstrated in one preliminary experiment. The results demonstrate a stable and functional in vitro preparation of intact perfused intercostal muscles in the pig.

(Received 20 January 2006; accepted after revision 27 April 2006; first published online 28 April 2006)
Corresponding author B. L. Pedersen: NMR Centre, The Panum Institute, Blegdamsvej 3, 2200 Copenhagen N, Denmark. Email: brlp{at}imbg.ku.dk