Nuclear Magnetic Resonance Spectroscopy of Living Systems: Applications in
Comparative Physiology.
Van Den Thillart, Guido, and Aren Van Waarde.
Institute of Evolutionary and Ecological Sciences and of Animal Physiology,
Gorlaeus Laboratories, University of Leiden, Leiden; and PET Center, Academic
Hospital, University of Gronigen, Gronigen, The Netherlands.
APStracts 2:0014P, 1996.
ABSTRACT
The most attractive feature of nuclear magnetic resonance spectroscopy (MRS)
is the noninvasive and nondestructive measurement of chemical compounds in
intact tissues. MRS already has many applications in comparative physiology,
usually based on observation of [sup]31[r]P, since the levels of P[inf]i[r]
indicate tissue energy status and are changed during exercise, fatigue,
recovery, hypometabolism, anesthesia, hypoxia, hypercapnia, and osmotic and
acid stress. Nuclei other than [sup]31[r]P may also be monitored, such as
[sup]1[r]H, [sup]13[r]C, [sup]15[r]N, [sup]19[r]F, or [sup]23[r]Na and applied
in biological research. Particularly, [sup]13[r]C-MRS is interesting because
it allows the analysis of metabolic pathways in living systems. Applications
of MRS in comparative physiology and biochemistry are comprehensively
discussed in this review. The main focus is on anaerobic metabolism during
hypoxia, ischemia, and exercise. Species as widely different as slime molds,
nematodes, frogs, turtles, and ducks have been studied by [sup]31[r]P-MRS. It
is not surprising that striking species differences do occur, but many
similarities are also observed. Unique is the occurrence of six different
phosphagens with different values of Gibbs free energy in polychete worms. The
presence of a particular phosphagen may be related to the average oxygen
tension within the tissues. Phosphagens and their kinases are also discussed
in relation to hypercapnia and acid stress. Other topics discussed in this
paper are enzyme kinetics, anesthetics, development and growth, parasitism,
and the detection of previously unknown compounds
APS Manuscript Number P-6.
Article publication pending July 1996, Physiological Reviews.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96