title: Streptozotocin (STZ) and schistosomiasis mansoni change the biodistribution of radiopharmaceutical sodium (99m)Tc-pertechnetate in mice.
abstract: Technetium-99m ((99m)Tc) is a radionuclide commonly used in nuclear medicine to obtain (99m)Tc-radiopharmaceuticals, which can be used to evaluate either physiological processes or changes related to diseases. It is also used in some experimental studies. Streptozotocin (STZ) administration to rodents causes lesions in very early stages and induces severe and permanent diabetes. Most morbidity of schistosomiasis mansoni is attributed to a granulomatous inflammatory response and associated liver fibrosis. This study was designed to investigate whether STZ administration and schistosomiasis modify the biodistribution of the radiopharmaceutical sodium (99m)Tc-pertechnetate.
  
  
  
  Adult female mice were infected by exposure to 100Schistosoma mansoni cercariae (BH strain, Belo Horizonte, Brazil) and euthanized after nine weeks. STZ was administered by a single intraperitoneal injection of 100mg/kg body weight, 3 or 15days before euthanasia. Each animal received 100μl of sodium (Na) (99m)Tc-pertechnetate ((99m)TcO4(-)) (740kBq). The animals were divided into four groups: A, uninfected; B, infected; C, uninfected + STZ; and D, infected + STZ. Blood, brain, thyroid, heart, lungs, liver, spleen, pancreas and kidneys were removed. The radioactivity was counted and the percentage of the injected dose of Na(99m)TcO4 per gram of the organ (% ID/g) was determined.
  
  
  
  Three days after the STZ injection, there was a decrease of Na(99m)TcO4 uptake by the liver, lungs, pancreas and kidneys (p<0.05) in group D when compared with group A. After 15days, the decrease of Na(99m)TcO4 uptake occurred also in the brain, thyroid, heart, spleen and blood (p<0.05) in group D.
  
  
  
  We demonstrated modifications on the biodistribution of Na(99m)TcO4 due to STZ administration and schistosomiasis, possibly due to physiological alterations in some organs.
  
  
  
  The biodistribution of radiopharmaceutical Na(99m)TcO4 should be carefully evaluated in subjects with diabetes and/or schistosomiasis infection.
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Av. Professor Manoel de Abreu, 444, 5° Andar, Vila Isabel, 20511-070 Rio de Janeiro, RJ, Brazil.
authors.forename: Vanessa Coelho
authors.initials: VC
authors.lastname: Góes
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Av. Professor Manoel de Abreu, 444, 5° Andar, Vila Isabel, 20511-070 Rio de Janeiro, RJ, Brazil.
authors.forename: Renata Heisler
authors.initials: RH
authors.lastname: Neves
authors.affiliation: Laboratório de Radiofarmácia Experimental, Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Av. 28 de Setembro, 87, 4° Andar fundos, Vila Isabel, 20551-030 Rio de Janeiro, RJ, Brazil.
authors.forename: Adriano
authors.initials: A
authors.lastname: Arnóbio
authors.affiliation: Laboratório de Radiofarmácia Experimental, Departamento de Biofísica e Biometria, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Av. 28 de Setembro, 87, 4° Andar fundos, Vila Isabel, 20551-030 Rio de Janeiro, RJ, Brazil.
authors.forename: Mario
authors.initials: M
authors.lastname: Bernardo-Filho
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia, Faculdade de Ciências Médicas, Universidade do Estado do Rio de Janeiro, Av. Professor Manoel de Abreu, 444, 5° Andar, Vila Isabel, 20511-070 Rio de Janeiro, RJ, Brazil. Electronic address: machado@uerj.br.
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Machado-Silva
mesh_terms: D000818:Animals; D005260:Female; D051379:Mice; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D012550:Schistosoma mansoni / Q000502:physiology*; D013670:Sodium Pertechnetate Tc 99m / Q000493:pharmacokinetics*; D013311:Streptozocin / Q000494:pharmacology*; D014018:Tissue Distribution / Q000187:drug effects
chemical_list: D019275:Radiopharmaceuticals; D013311:Streptozocin; D013670:Sodium Pertechnetate Tc 99m
keywords: Biodistribution; Diabetes mellitus; Schistosomiasis mansoni; Sodium (99m)Tc-pertechnetate; Streptozotocin; Technetium-99m