Góes Vanessa Coelho, Neves Renata Heisler, Arnóbio Adriano, Bernardo-Filho Mario, Machado-Silva José Roberto
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.
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.
Nucl Med Biol. 2016 Sep;43(9):581-586. doi: 10.1016/j.nucmedbio.2016.06.003. Epub 2016 Jun 27.
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.
锝-99m（99mTc）是核医学中常用的一种放射性核素，用于制备99mTc放射性药物，可用于评估生理过程或与疾病相关的变化。它也用于一些实验研究。给啮齿动物注射链脲佐菌素（STZ）会在早期导致损伤并诱发严重且永久性的糖尿病。曼氏血吸虫病的大多数发病率归因于肉芽肿性炎症反应和相关的肝纤维化。本研究旨在调查注射STZ和感染血吸虫病是否会改变放射性药物高锝酸钠（99mTcO4-）的生物分布。
成年雌性小鼠通过接触100条曼氏血吸虫尾蚴（BH株，巴西贝洛奥里藏特）感染，9周后安乐死。在安乐死前3天或15天，通过腹腔注射100mg/kg体重的STZ。每只动物接受100μl高锝酸钠（99mTcO4-）（740kBq）。动物分为四组：A组，未感染；B组，感染；C组，未感染+STZ；D组，感染+STZ。取出血液、脑、甲状腺、心脏、肺、肝、脾、胰腺和肾脏。计数放射性，并测定每克器官中99mTcO4注射剂量的百分比（%ID/g）。
与A组相比，D组在注射STZ后3天，肝脏、肺、胰腺和肾脏对99mTcO4的摄取减少（p<0.05）。15天后，D组的脑、甲状腺、心脏、脾脏和血液中99mTcO4的摄取也减少（p<0.05）。
我们证明了由于注射STZ和感染血吸虫病，99mTcO4的生物分布发生了改变，这可能是由于某些器官的生理改变所致。
对于糖尿病和/或血吸虫病感染的患者，应仔细评估放射性药物99mTcO4的生物分布。
