Technetium-99m (^99mTc) is a radionuclide that has negligible enviromnental
impact, is easily available, inexpensive and can be used as a radioactive
tracer in biological experiences. In order to know the mode of action of
sodium phenobarbital in moving adult Schistosoma mansoni worms from
mesenteric veins to the liver, we labelled sodium phenobarbital (PBBT) with
^99mTc and a biodistribution study in infected and non-infected Swiss mice
was performed. The PBBT was incubated with stannous chloride used as
reducing agent and with ^99mTc, as sodium pertechnetate. The radioactivity
labelling (%) was determined by paper ascending chromatography perfomed
with acetone (solvent). The ^99mTc-PBBT was administered by intraperitoneal
route to Swiss mice infected eight weeks before. The animals were perfused
after diferent periods of time (0,1,2,3,4 hr) when blood, spleen, liver,
portal vein, mesenteric veins, stomach, kidneys and adult worms were
isolated. The radioactivity present in these samples was counted in a well
counter and the percentage was determined. The radioactivity was mainly
taken up by the blood, kidney, liver and spleen. No radioactivity was found
on the adult worms. We concluded that the worm shift was due to an action
on the host of the sodium phenobarbital.
