Biodistribution of labeled rifampicin in animals
The Institutional Animal Ethical Committee approved the study, and the
treatment of the animals was carried out in accordance with the
Committee for the Purpose of Control and Supervision of Experiments on
Animals’ recommendations (CPCSEA). Wistar rats (n=12) weighing 150-250 g
were orally administered 4mg/kg rifampicin dissolved in 1ml of vehicle
containing 100-200 µCi of activity of 99mTc. “Tissues
and organs were excised from the rats following sacrifice by cervical
dislocation at” pre-defined time points of 0.5h, 4h, and 8h post-oral
administration of radiolabeled rifampicin. “Three rats were used for
each time point. The radioactivity in each organ/tissue was measured”
using “a flat-type solid scintillation counter (15-cm diameter) with a
NaI(Tl) detector. The percentage of administrated activity (%AD) in
each organ as well as per g of the tissue” was calculated. “Blood,
bone, and muscle weight were taken as 7%, 6.5%, and 40% of the body
weight, respectively”.