Interrelation of oxidative metabolism and local perfusion
demonstrated by nmr in human skeletal muscle.
Toussaint, Jean-Fran[cedilla]cois, Kenneth K. Kwong, Fidelis M'kparu,
Robert M. Weisskoff, Paul J. Laraia, Howard L. Kantor.
CEA-SHFJ, NMR Center, Orsay, France (JFT), the Cardiac Unit (JFT,
FMK, PJL, HLK), and NMR Center (JFT, KKK, RMW, HLK), Massachusetts
General Hospital, Boston, MA
APStracts 3:0361A, 1996.
Using NMR, we have examined the relationship of high energy phosphate
metabolism and perfusion in human soleus and gastrocnemius muscles
(S&G). With 31P-NMR spectroscopy, we monitored phosphocreatine
(PCr) decay and recovery in 8 normal volunteers and 4 heart failure
(HF) patients performing ischemic plantar flexion. Using echo-planar
imaging (EPI), perfusion was independently measured by a local
(inversion-recovery, T1-Flow) and a regional technique (NMR
-Plethysmography: NMR-P). After correction for its pH dependence, PCr
recovery time constant (PCrTC) is 27.5 +/- 8.0 s in normal
volunteers, with mean flow 118+/-75 ml/100ml/min (S&G T1-Flow) and
30.2 +/- 9.7 ml/100ml/min (NMR-P flow). We demonstrate a positive
correlation between PCrTC and local perfusion given by y = 50 - 0.15
x (r2 = 0.68, p = 0.01) for the 8 normal subjects, and y = 64 - 0.24x
(r2 = 0.83, p = 0.0001) for the 12 subjects recruited in the study.
Regional perfusion techniques also show a significant but weaker
correlation. Using this totally non-invasive method, we conclude that
aerobic ATP resynthesis is related to the magnitude of perfusion i.e.
O2 availability, and demonstrate that MRI and MRS together can
accurately assess muscle functional status.
Received 11 July 1995; accepted in final form 25 March 1996.
APS Manuscript Number A751-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 21 August 1996