Planar myocardial imaging in the baboon model with iodine-123-15-(iodophenyl)pentadecanoic acid (IPPA) and iodine-123-15-(P-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP), using time-activity curves for evaluation of metabolism.
The purpose of this study was to compare by planar myocardial scintigraphy the kinetics of iodine-123-15-(iodophenyl)pentadecanoic acid (123I-pPPA and 123I-oPPA), and of iodine-123-(p-iodophenyl)-3-R,S-methyl-pentadecanoic acid (BMIPP), firstly in normal baboons, and subsequently after blocking fatty acid oxidation by a carnitine palmitoyl transferase I(CPT1) inhibitor. The induced changes in myocardial metabolism were reflected in the dynamic behaviour of the three tracers. pPPA and oPPA to a large extent, provided information on beta-oxidation changes in the myocardium: beta-oxidation participation changed from 47% and 50%, respectively to 17% and 23% after inhibition. BMIPP provided better images and reflected largely on changed tracer incorporation into the neutral lipid pools. The beta-oxidation contributed only about 10% towards the metabolic pathway of BMIPP. The information obtained in this study could help determine the tracer of choice for SPECT, whereby myocardial viability could optimally be revealed.
Dormehl
I C
IC
Institute for Life Sciences, University of Pretoria, South Africa.
Hugo
N
N
Rossouw
D
D
White
A
A
Feinendegen
L E
LE
D000818:Animals; D002334:Carnitine O-Palmitoyltransferase / Q000037:antagonists & inhibitors; D003652:Decanoic Acids / Q000493:pharmacokinetics*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004852:Epoxy Compounds / Q000494:pharmacology; D005227:Fatty Acids / Q000378:metabolism; D006321:Heart / Q000000981:diagnostic imaging* / Q000187:drug effects; D007004:Hypoglycemic Agents / Q000494:pharmacology; D007457:Iodine Radioisotopes; D007462:Iodobenzenes / Q000493:pharmacokinetics*; D008099:Liver / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D010215:Papio; D013329:Structure-Activity Relationship; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
D003652:Decanoic Acids; D004791:Enzyme Inhibitors; D004852:Epoxy Compounds; D005227:Fatty Acids; D007004:Hypoglycemic Agents; D007457:Iodine Radioisotopes; D007462:Iodobenzenes; C049338:iodofiltic acid; C025391:omega-(4-iodophenyl)pentadecanoic acid; D002334:Carnitine O-Palmitoyltransferase; C054207:etomoxir