Kinetics of a putative hypoxic tissue marker, technetium-99m-nitroimidazole (BMS181321), in normoxic, hypoxic, ischemic and stunned myocardium

J Nucl Med. 1994 Aug;35(8):1371-6.

Abstract

This study focused on the kinetics of the newly developed 99mTc-nitroimidazole, propyleneamine oxime-1,2-nitroimidazole (BMS181321) in the different setting of myocardial perfusion states and oxygenation levels, and compared the kinetics of BMS181321 with those of other technetium analogues.

Methods: The kinetics of BMS181321 were evaluated in isolated perfused rat hearts. Technetium-99m-hexamethylpropyleneamine oxime (HMPAO) and a non-nitroimidazole-containing analogue of BMS181321 (6-methyl propyleneamine oxime; PAO-6-Me) were used to compare their kinetics with those of BMS181321.

Results: BMS181321 cleared quickly from normoxic hearts and the retention in the myocardium 10 min after injection was 0.84% +/- 0.04% ID/g wet wt (mean +/- s.e.m.). In contrast, BMS181321 was retained after reperfusion when it was injected before ischemia; the uptake in the myocardium 10 min after reperfusion was significantly greater than in controls (23.9% +/- 3.9% ID/g wt, p < 0.05).

Conclusions: These results indicate that 99mTc-BMS181321 is well trapped in ischemic myocardium and moderately trapped in hypoxic myocardium, but washed out quickly in stunned myocardium. The residence time influences the amount retained.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Female
  • Heart / diagnostic imaging*
  • Myocardial Ischemia / diagnostic imaging*
  • Myocardial Stunning / diagnostic imaging*
  • Myocardium / metabolism
  • Nitroimidazoles* / pharmacokinetics
  • Organotechnetium Compounds* / pharmacokinetics
  • Oximes
  • Oxygen Consumption / physiology
  • Perfusion
  • Radionuclide Imaging
  • Rats
  • Technetium Tc 99m Exametazime

Substances

  • Nitroimidazoles
  • Organotechnetium Compounds
  • Oximes
  • BMS 181321
  • 6-methyl propyleneamine oxime
  • Technetium Tc 99m Exametazime