Biodistribution of TC-99m sestamibi in rats utilizing whole-body autoradiography
- Univ. of Virginia Health Sciences Center, Charlottesville, VA (United States); and others
Current biodistribution models for Tc-99m sestamibi (MIBI) rely on gross imaging methods via Anger camera or at best, excision of animal tissue and counting tissue samples. These methods do not allow for detection of intra-organ inhomogeneities and small accumulations of activity are often treated as nonspecific background. The goal of this work was to examine the biodistribution of MIBI using whole-body autoradiography to obtain very detailed activity distribution information. Four anesthetized albino rats (300 g {plus_minus}10 g ) were injected into a dorsal metatarsal vein with an average of 333 MBq MIBI. One rat each was sacrificed at 5, 20, 60 and 180 minutes post-injection. Animals were embedded, frozen and slices (50-100 {mu}m thick) were obtained using a PMV-2250 macro-cryo-microtome and autoradiographs were made of slices. Cardiac uptake remained consistently high at all time points. All muscular areas exhibited uptake, including the diaphragm and GI tract wells. Significant MIBI uptake was observed in many different glands, including the submaxillary, suprarenal, thymus, lacrimal, harderian and thyroid. Pancreatic uptake was observed at each time. MIBI cleared from the liver and spleen quickly, with significant activity in the bowel at 5 minutes. High small bowel content activity was observed at all time points. The contents of the distal stomach and colon accumulated activity in all but the 5 minute studies. Clearance from the kidneys occurred between 1 and 3 hours, although kidney activity remained similar to the heart at 3 hours. Bladder activity was observed as early as 20 minutes, with the highest at the 3 hour time point. Very slight testicular uptake was observed in the epidydmis and wall of the scrotal sac. Although these autoradiographs confirm existing kinetics, they provide a unique, high-resolution record of previously unknown MIBI deposition areas such as the pancreas and GI tract lining.
- OSTI ID:
- 198020
- Report Number(s):
- CONF-940605--
- Journal Information:
- Journal of Nuclear Medicine, Journal Name: Journal of Nuclear Medicine Journal Issue: Suppl.5 Vol. 35; ISSN 0161-5505; ISSN JNMEAQ
- Country of Publication:
- United States
- Language:
- English
Similar Records
EFFECT OF D$sub 2$O IN VIVO AND IN VITRO ON UPTAKE OF p-AMINOHIPPURATE BY RAT KIDNEY SLICES
The influence of MDP on Ga-67 distribution in vivo