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Background: The biological effects of cigarette smoke are not fully known. To improve our understanding of the action of various chemical agents, we investigated the biodistribution of sodium pertechnetate (Na 99m TcO 4 ) in mice exposed to cigarette smoke.

28 de setembro, 87, Rio de Janeiro, RJ, Brasil, 2055 1-030. bemardo@uerj.br key words: Sechiunz edule, blood cells, technetium-99m, biodistribution, morphometry. summary.The evidence that drugs can affect radiolabeling or biodistribution of red cells in setting of nuclear medicine clinic has with to light only recently. A therapeutic drug can modify the nature/amount of technetium-99m ehTc) radiopharmaceutical bound to blood elements and this may result in a unexpected behavior of the radiopharmaceutical. Chayotte is used as food or as medication in popular medicine. We evaluated the influence of chayotte extract (macerated) on the biodistribution of sodium pertechnetate (gh"Tc04Na) in rats lVistar and on the morphometry of the red blood cells. The animals were treated during 60 days with chayotte extract. After that, Tc04Na was injected and the animals were sacrificed. The organs were isolated and counted in a well counter. The percentages of radioactivity (%AT0 in the organs were calculated. The analysis of the results have shown that there was a decrease of %AT1 in the lungs, stomach and thyroid. Histological preparations were carried out with the blood samples from the animals treated with chayotte during 15 days. Optical microscopy of red blood cells (RBC) showed important morphological alterations due to the treatment of the animals during 15 days with chayotte extract. The results could be justified by the metabolization of chayotte vegetable that could be capable to induce the generation of active metabolites with lesive properties in specific biological systems. The effects of the chayotte extract could also be due to a direct action of the compounds present in extract.

RESUMO: "Infl uência da bifl orina na marcação do tecnécio-99m em células vermelhas do sangue, proteínas do plasma, proteínas celulares e em linfócitos: estudos in vitro". Neste artigo relatam-se os resultados de um estudo in vitro envolvendo a infl uência da bifl orina (uma o-quinona isolada de Capraria bifl ora L. que possui uma potente atividade antimicrobiana) na marcação do Tc-99m em células vermelhas do sangue, proteínas do plasma, proteínas celulares e em linfócitos. O sangue foi coletado de ratos Wistar e incubado com várias concentrações de bifl orina, e soluções de cloreto estanoso (SnCl 2 ) adicionando-se Tc-99m. O plasma (P) e as células vermelhas do sangue (CVS) foram isolados, precipitados e centrifugados, isolando-se as frações solúveis (FS) e insolúveis (FI). A maior concentração de bifl orina (100%) é capaz de reduzir a captação do Tc-99m (%ATI) nas CVS e a fi xação na FI-P. Uma solução de 0,2 mL de linfócitos (2,5 mL; 1.0 x 10 6 células/mL), obtidos por centrifugação de sangue humano tratado com Ficoll-Hypac, foi incubada com bifl orina (0,1 mL). Soluções de cloreto estanoso e Tc-99m foram então adicionadas. Os linfócitos foram separados e o %ATI presente nessas células foi avaliado. Uma redução no %ATI (de 97,85 ± 0,99 a 88,86 ± 5) foi observada para CVS e para FI-P (73,24 ± 5,51 a 20,72 ± 6,95). Os resultados não mostraram decréscimo no %ATI para os linfócitos com bifl orina.Unitermos: Capraria bifl ora, radiofarmacêuticos, pertecnetato de sódio. ABSTRACT:In this paper we report the results of an in vitro study involving the infl uence of bifl orin (an o-quinone isolated from Capraria bifl ora L. that has potent antimicrobial activity) on the Tc-99m labeling of red blood cells, plasma protein, cells protein, and lymphocytes. Blood was withdrawn from Wistar rats and incubated with various concentrations of bifl orin, and solutions of stannous chloride and Tc-99m were added. Plasma (P) and red blood cells (RBC) were isolated, precipitated, and centrifuged, and soluble (SF) and insoluble (IF) fractions were isolated. The results show that the highest concentration (100%) of bifl orin is able to reduce the uptake of Tc-99m (%ATI) on RBC and the fi xation on IF-P. To study the infl uence of bifl orin on 99mTc lymphocyte labeling, human blood was submitted to a technique with Ficoll-Hypac and centrifuged, and white cells were isolated. Lymphocytes (2.5 mL; 1.0 x 10 6 cells/mL) were obtained and a 0.2 mL solution was incubated with bifl orin (0.1 mL). Solutions of stannous chloride and 99mTc were added. Lymphocytes were separated and the %ATI bound in these cells was evaluated. A reduction in %ATI (from 97.85 ± 0.99 to 88.86 ± 5) was observed for RBC and for IF-P (73.24 ± 5.51 to 20.72 ± 6.95). In this case the results showed no decrease in %ATI for the lymphocytes with bifl orin.

There is evidence that the biodistribution of radiopharmaceuticals may be altered by a variety of drugs. If unknown, the drug interaction with radiopharmaceuticals can lead to misdiagnosis or the necessity to repeat the examination, increasing the dose to the patient. Different substances has the ability to modify the electrophoretic mobility of the deovibonucleic acid (DNA). Cauliflower has the leaves used in folk medicine. We evaluated the influence of the leaf extract of cauliflower on: (i) the biodistribution of the radiopharmaceutical sodium pertechnetate (99"Tc04Na) and in (ii) the mobility of a plasmid pUC 9.1 through gel electrophoresis analysis. 99"TcOjNa (0.3ml) was administered into female Wistur rats which had drunk or not the extract for 60 days. AAer 10 min, the animals were sacrificed, the organs isolated, the radioactivity determined in a well counter and the percentages of radioactivity per gam (%ATl/g) in the organs calculated. The %ATI/g was not significantly altered (p>0.05) in the treated animals. The supercoiled form of the plasmid was modified by the cauliflower extract. We suggest that the action of this extract on the DNA might be explained by a direct effect or by the generation of reactive oxygen species (ROS) that could be inducing lesions in the plasmid DNA. However, this Iesive effect was not capable to alter the biodistribution of the 99"Tc04Na in the treated animals with the extract. ,IntroductionRadiopharmaceuticals are designed to have specific biodistribution and uptake in determined targets and/or elimination patterns when administered to normal subjects. The altered biologic behavior helps a physician to make a diagnosis (1). Altered biologic behavior may also be due to interferences caused by pharmacodynamic effects of drugs (2). Various substances, as the stannous ions, have the property to induce alterations on the deoxyribonucleic acid (DNA) molecule (3). Cauliflower in fok medicine, has its leaves used to treat a variety of diseases (4). The purpose of this study was to evaluate the effect of the leaf extract of the cauliflower (i) on the biodistribution of the radiopharmaceutical 99"Tc04Na in female FVistar rats and (ii) on the topology on gel electrophoresis of plasmid DNA submitted to SnClt (5). Results and discussionThe effect of the leaf extract of cauliflower in the uptake (%AWg) of 99"Tc04Na in the isolated organs from female Wistar rats which had drunk (treated group) or not