Biodistribution of the radiophamarceutical sodium pertechnetate (Na99mTcO4) after massive small bowel resection in rats

Abstract

Purpose:To evaluate the biodistribution of sodium pertecnetate (Na 99m TcO 4 ) in organs and tissues, the morphometry of remnant intestinal mucosa and ponderal evolution in rats subjected to massive resection of the small intestine. Methods: Twenty-one Wistar rats were randomly divided into three groups of 7 animals each. The short bowel (SB) group was subjected to massive resection of the small intestine; the control group (C) rats were not operated on, and soft intestinal handling was performed in sham rats. The animals were weighed weekly. On the 30th postoperative day, 0.l mL of Na 99m TcO 4 , with mean activity of 0.66 MBq was injected intravenously into the orbital plexus. After 30 minutes, the rats were killed with an overdose of anesthetic, and fragments of the liver, spleen, pancreas, stomach, duodenum, small intestine, thyroid, lung, heart, kidney, bladder, muscle, femur and brain were harvested. The biopsies were washed with 0.9% NaCl.,The radioactivity was counted using Gama Counter Wizard TM 1470, PerkinElmer. The percentage of radioactivity per gram of tissue (%ATI/g) was calculated. Biopsies of the remaining jejunum were analysed by HE staining to obtain mucosal thickness. Analysis of variance (ANOVA) and the Tukey test for multiple comparisons were used, considering p<0.05 as signifi cant. Results: There were no signifi cant differences in %ATI/g of the Na 99m TcO 4 in the organs of the groups studied (p>0.05). An increase in the weight of the SB rats was observed after the second postoperative week. The jejunal mucosal thickness of the SB rats was signifi cantly greater than that of C and sham rats (p<0.05). Conclusion: In rats with experimentally-produced short bowel syndrome, an adaptive response by the intestinal mucosa reduced weight loss. The biodistribution of Na 99m TcO 4 was not affected by massive intestinal resection, suggesting that short bowel syndrome is not the cause of misleading interpretation, if an examination using this radiopharmaceutical is indicated. Key words: Short Bowel Syndrome. Sodium Pertechnetate Tc 99m. Pharmacokinetics. Rat RESUMO Objetivo: Avaliar em modelo animal com ressecção extensa do intestino delgado a biodistribuição de pertecnetato de sódio (Na 99m TcO 4 ) em órgãos e tecidos, a evolução ponderal e a morfometria da mucosa do intestino delgado remanescente. Métodos: Vinte e um ratos Wistar foram aleatoriamente divididos em três grupos de sete animais cada. O grupo intestino curto (IC) foi submetido a ressecção extensa do intestino delgado, o grupo controle (C) não foi operado e o grupo sham foi submetido a leve manipulação cirúrgica das alças intestinais.Todos foram pesados semanalmente. No 30º dia pós-operatório foi administrado 0,l mL de Na 99m TcO 4 aos animais dos três grupos, IV no plexo orbital, com atividade radioativa média de 0,66MBq. Após 30 minutos os ratos foram mortos e retirados fragmentos do fígado, baço, pâncreas, estomago, duodeno, intestino delgado, tireóide, pulmão, coração, rim, bexiga, músculo, fêmur, e cérebro. As amostra...

The ileum as a determinant organ of the functional liver cell mass in rats

“…To evaluate functional liver mass, we used pertechnetate labeled phytate, a radiocolloid which biodistribution has already been studied and validated in the assessment of liver function in postoperative period of intestinal resection in an animal model 8 . In the present study we observed a significant reduction of functional liver capacity in rats subjected to ileum resection, examined by measuring aspartate aminotransferase (AST) and alanine aminotransferase (ALT), intracellular enzymes released in the interstitium and circulation after hepatocytes injury 16 .…”

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Biodistribution of samarium-153-EDTMP in rats treated with docetaxel

“…Many factors, such as drug therapy, radiation therapy, surgery, in addition to the pathological process, could affect the biodistribution of different radiopharmaceuticals [13][14][15] . In this work, when Sm-153-EDTMP was administered to rats previously treated with docetaxel, the biodistribution of the radiopharmaceutical to bone, kidney, liver and lung was significantly lower than that of controls.…”

Biodistribution of technetium-99m pertechnetate after Roux-en-Y gastric bypass (Capella technique) in rats

“…Examination of gastric emptying, liver function, thyroid function, bone disorders, distant metastasis, etc, are used frequently in patients undergoing bariatric surgery 10 . Radiopharmaceuticals biodistribution may provide important information about its uptake to some target organs, but post-surgery data are scarce 11 . It is relevant to investigate technetium-99m pertechnetate biodistribution after RYGB, because it is highly secreted by gastric mucosa.…”