Comparison of binding of [3H]misonidazole and [14C]misonidazole in multicell spheroids

J. S. Rasey, Z. Grunbaum, K. Krohn

Research output: Contribution to journalArticlepeer-review

28 Scopus citations


Uptake of [2-ring-14C]misonidazole and [3H]misonidazole with tritium in the side chain has been compared in 1-mm EMT-6/UW spheroids using liquid scintillation counting and autoradiography. The uptake of both labeled sensitizers as a function of incubation time was virtually identical. Uptake by the spheroids exceeded levels in the medium by 1 1/2 to 2 hr and was well modeled as a first-order binding process, with rate constants of 0.00324 hr-1 for 3H and 0.00388 hr-1 for 14C. The similar uptake of the two versions of this sensitizer labeled in different positions suggest that the metabolic actions which allow the drug to bind in hypoxic cells do not principally involve metabolites which separate the number 2 carbon of the imidazole ring from the side chain. The pattern of silver grains in autoradiographs was similar for both labeled sensitizers, with most labeled drug bound in an intermediate zone of cells between the necrotic center and the actively proliferating rim of the spheroids. The superior resolution possible with the tritiated compound showed that both nucleus and cytoplasm in viable looking cells were labeled while pycnotic cells were not labeled.

Original languageEnglish (US)
Pages (from-to)473-479
Number of pages7
JournalRadiation research
Issue number3
StatePublished - 1985
Externally publishedYes

ASJC Scopus subject areas

  • Biophysics
  • Radiation
  • Radiology Nuclear Medicine and imaging


Dive into the research topics of 'Comparison of binding of [3H]misonidazole and [14C]misonidazole in multicell spheroids'. Together they form a unique fingerprint.

Cite this