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

PURPOSE: To evaluate if the ileum resection changes the functioning liver cell mass, the hepatic metabolism and the biodistribution of radiopharmaceutical in rats. METHODS: Twelve Wistar rats weighing 285g±34g were randomly divided into the ileum resection group (n = 6) and sham group rats (n = 6). After 30 days, they were anesthetized and 0.1mL of 99m-Tc-phytate(0.66MBq) was injected via femoral vein. After 30 minutes, blood samples were collected for red blood cells radioactive labeling and serum ALT, AST and gammaGT. Liver samples were used for 99m-Tc-phytatepercentage of radioactivity/gram of tissue and histopathology. Student’s t test was used with significance 0.05. RESULTS: There was a higher uptake of 99m-Tc-phytate in the liver of sham rats, compared to the ileum resection group (p<0.05). GammaGT, ALT and AST were increased in ileum resection rats compared to sham (p<0.05). The he patocytes count was significantly lower in ileum resection group than in sham (p<0.05). Liver: body mass ratio was lower in experimental animals than in sham group (p<0.05). CONCLUSION: These data support that the ileum has important role in liver function and liver mass regulation, and they have potential clinical implications regarding the pathogenesis of liver injury following lower bowel resection.

Efeitos de um extrato aquoso de porangaba (Cordia salicifolia) na marcação de constituintes sanguíneos com tecnécio-99m e na morfologia de hemácias

Effects of a Cordia salicifolia (porangaba) extract on the labeling of blood cells (BCs) with technetium-99m ((99m)Tc) and on the morphology of red BCs were evaluated. Labeling of cellular and molecular structures with (99m)Tc depends on a reducing agent. Some physical characteristics, as visible absorbance spectrum, electric conductivity, and refractive index of this porangaba extract, were also determined. Blood samples from Wistar rats were incubated with porangaba extract or with 0.9% NaCl (control). Labeling of blood constituents with (99m)Tc was performed. Plasma (P) and BCs, both soluble (SF-P and SF-BC) and insoluble (IF-P and IF-BC) fractions, were separated. The radioactivity in each fraction was counted, and the percentage of radioactivity incorporated (%ATI) was calculated. Blood smears were prepared, fixed, and stained, and the morphology of the red BCs was evaluated. Data showed an absorbance peak at 480 nm and electric conductibility and refractive index concentration-dependent. Porangaba extract decreased significantly (P < .05) the BC, IF-P, and IF-BC %ATI, and no modifications were verified on the shape of red BCs. Analysis of the results reveals that some physical parameters could be useful to aid in characterizing the extract studied. Moreover, it is possible that chemical compounds of this extract could have chelating/redox actions or be capable of binding to plasma and/or cellular proteins

Efeito de um extrato de Ganoderma lucidum (Reishi) na marcação de constituintes sanguíneos com tecnécio-99M e na sobrevivência de Escherichia coli

Clinical evaluations have been made possible with radiobiocomplexes marked with tecnecium-99m (99mTc). Natural or synthetic drugs are able to interfere in the marking of blood structures with 99m Tc. Also, the toxicity of several natural products has been described. The aim of this study was evaluating the effect of an extract of Ganoderma lucidum (Reishi) in the marking of blood constituents with 98m Tc and in the survival of Escherichia coli. Blood samples from Wistar rats were treated with reishi extract. Radiomarking procedure was performed. Samples of plasma (P), blood cells (CS), and insoluble (FI) and soluble (FS) fractions of P and CS were separated and the radioactivity was counted to determine radioactivity percentages (%ATI). Escherichia coli AB1157 cultures were treated with stannous chloride in the presence and absence of the reishi extract. Blood samples and bacterial cultures treated with NaCl 0.9% were used as controls. Data indicated that the reishi extract has significantly altered (p<0,05) the %ATI of P, CS, FI-P, FS-P, FI-CS e FS-CS, as well as it has increased survival of bacterial cultures treated with stannous chloride. Our results suggest that the Reishi extract would be able to present a redox/ chelant action by altering blood constituent marking with 99mTc and by protecting bacterial cultures against stannous chloride-induced oxydating lesions. The study had a multidisciplinary character, with the participation of the following areas of knowledge: Biophysics, Radiobiology, Botanics, Phytotherapy, and Hematology

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

PURPOSE: To evaluate if the ileum resection changes the functioning liver cell mass, the hepatic metabolism and the biodistribution of radiopharmaceutical in rats. METHODS: Twelve Wistar rats weighing 285g±34g were randomly divided into the ileum resection group (n = 6) and sham group rats (n = 6). After 30 days, they were anesthetized and 0.1mL of 99m-Tc-phytate(0.66MBq) was injected via femoral vein. After 30 minutes, blood samples were collected for red blood cells radioactive labeling and serum ALT, AST and gammaGT. Liver samples were used for 99m-Tc-phytatepercentage of radioactivity/gram of tissue and histopathology. Student’s t test was used with significance 0.05. RESULTS: There was a higher uptake of 99m-Tc-phytate in the liver of sham rats, compared to the ileum resection group (p<0.05). GammaGT, ALT and AST were increased in ileum resection rats compared to sham (p<0.05). The he patocytes count was significantly lower in ileum resection group than in sham (p<0.05). Liver: body mass ratio was lower in experimental animals than in sham group (p<0.05). CONCLUSION: These data support that the ileum has important role in liver function and liver mass regulation, and they have potential clinical implications regarding the pathogenesis of liver injury following lower bowel resection.

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

The biodistribution of sodium pertechnetate, the most used radiopharmaceutical in nuclear medicine, has not been studied in details after bariatric surgery. The objective was to investigate the effect of Roux-en-Y gastric bypass (RYGB) on biodistribution of sodium pertechnetate (Na99mTc-) in organs and tissues of rats. Methods: Twelve rats were randomly divided into two groups of 6 animals each. The RYGB group rats were submitted to the Roux-en-Y gastric bypass and the control group rats were not operated. After 15 days, all rats were injected with 0.1mL of Na99mTc- via orbital plexus with average radioactivity of 0.66 MBq. After 30 minutes, liver, stomach, thyroid, heart, lung, kidney and femur samples were harvested, weighed and percentage of radioactivity per gram (%ATI/g) of each organ was determined by gama counter Wizard Perkin-Elmer. We applied the Student t test for statistical analysis, considering p<0.05 as significant. Results: Significant reduction in mean %ATI/g was observed in the liver, stomach and femur in the RYGB group animals, compared with the control group rats (p<0.05). In other organs no significant difference in %ATI/g was observed between the two groups. Conclusion: This work contributes to the knowledge that the bariatric surgery RYGB modifies the pattern of biodistribution of Na99mTc

Biodistribution of the Radiopharmaceutical Technetium- 99m-Sodium Phytate in Rats After Splenectomy

Drugs and surgery can interfere with the biodistribution of radiopharmaceuticals and data about the effect of splenectomy on the metabolism of phytate-Tc-99m are scarce. This study aimed at evaluating the interference of splenectomy on phytate-Tc-99m biodistribution and liver function in rats. The SP group rats (n=6) underwent splenectomy. In group C (control) the animals were not operated on. After 15 days, all rats were injected with 0.1mL of Tc-99m-phytate via orbital plexus (0.66MBq). After 30 minutes, liver samples were harvested, weighed and the percentage of radioactivity per gram (%ATI-g) was determined by a Wizard Perkin-Elme gama counter. The ATI%-g in splenectomized rats (0.99±0.02) was significantly higher than in controls (0.4±0.02), (p=0.034). ALT, AST and HDL were significantly lower in SP rats (p= 0.001) and leukocytosis was observed in SP rats. In conclusion, splenectomy in rats changed the hepatic biodistribution of Tc-99m-phytate and liver enzimatic activity

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

The biodistribution of sodium pertechnetate, the most used radiopharmaceutical in nuclear medicine, has not been studied in details after bariatric surgery. The objective was to investigate the effect of Roux-en-Y gastric bypass (RYGB) on biodistribution of sodium pertechnetate (Na99mTc-) in organs and tissues of rats. Methods: Twelve rats were randomly divided into two groups of 6 animals each. The RYGB group rats were submitted to the Roux-en-Y gastric bypass and the control group rats were not operated. After 15 days, all rats were injected with 0.1mL of Na99mTc- via orbital plexus with average radioactivity of 0.66 MBq. After 30 minutes, liver, stomach, thyroid, heart, lung, kidney and femur samples were harvested, weighed and percentage of radioactivity per gram (%ATI/g) of each organ was determined by gama counter Wizard Perkin-Elmer. We applied the Student t test for statistical analysis, considering p<0.05 as significant. Results: Significant reduction in mean %ATI/g was observed in the liver, stomach and femur in the RYGB group animals, compared with the control group rats (p<0.05). In other organs no significant difference in %ATI/g was observed between the two groups. Conclusion: This work contributes to the knowledge that the bariatric surgery RYGB modifies the pattern of biodistribution of Na99mTc

Biodistribution of the Radiopharmaceutical Technetium- 99m-Sodium Phytate in Rats After Splenectomy

Drugs and surgery can interfere with the biodistribution of radiopharmaceuticals and data about the effect of splenectomy on the metabolism of phytate-Tc-99m are scarce. This study aimed at evaluating the interference of splenectomy on phytate-Tc-99m biodistribution and liver function in rats. The SP group rats (n=6) underwent splenectomy. In group C (control) the animals were not operated on. After 15 days, all rats were injected with 0.1mL of Tc-99m-phytate via orbital plexus (0.66MBq). After 30 minutes, liver samples were harvested, weighed and the percentage of radioactivity per gram (%ATI-g) was determined by a Wizard Perkin-Elme gama counter. The ATI%-g in splenectomized rats (0.99±0.02) was significantly higher than in controls (0.4±0.02), (p=0.034). ALT, AST and HDL were significantly lower in SP rats (p= 0.001) and leukocytosis was observed in SP rats. In conclusion, splenectomy in rats changed the hepatic biodistribution of Tc-99m-phytate and liver enzimatic activity

Effect of sildenafil in renal ischemia/reperfusion injury in rats

To evaluate the effect of sildenafil, administered prior to renal ischemia/reperfusion (I/R), by scintigraphy and histopathological evaluation in rats. Methods: Twenty-four rats were divided randomly into two groups. They received 0.1 ml of 99mTechnetium-etilenodicisteine intravenous, and a baseline (initial) renal scintigraphy was performed. The rats underwent 60 minutes of ischemia by left renal artery clamping. The right kidney was not manipulated. The sildenafil group (n=12) received orally 1 mg/kg of sildenafil suspension 60 minutes before ischemia. Treatment with saline 0.9% in the control group (n=12). Half of the rats was assessed after 24 hours and half after seven days I/R, with new renal scintigraphy to study differential function. After euthanasia, kidneys were removed and subjected to histopathological examination. For statistical evaluation, Student t and Mann-Whitney tests were used. Results: In the control group rats, the left kidneys had significant functional deficit, seven days after I/R, whose scintigraphic pattern was consistent with acute tubular necrosis, compared with the initial scintigraphy (p<0.05). Sildenafil treatment resulted in better differential function of the left kidneys 24h after reperfusion, compared with controls. Histopathologically, the left kidney of control rats (24 hours after I/R) showed a higher degree of cellular necrosis when compared with the sildenafil treated rats (p<0.05). Conclusion: Sildenafil had a protective effect in rat kidneys subjected to normothermic I/R, demonstrated by scintigraphy and histomorphometry

Influence of Splenectomy on the Biodistribution of Technetium-99m Dimercaptosuccinic Acid (99mTc-DMSA) in Rats

This study aimed to evaluate if the splenectomy alters the biodistribution of 99mTc-DMSA and renal function in Wistar rats. The animals were separated in the groups: splenectomy (n = 6) and control (n = 6). After splenectomy (15 days), the administration of 0.1ml of 99mTc-DMSA IV (0.48 MBq) was carried out. Thirty minutes later, kidney, heart, lung, thyroid, stomach, bladder and femur and samples of blood were isolated. The organs were weighed, counted and the percentage of radioactivity -g (%ATI-g) determined. Serum urea and creatinine, hematocrit, leukocytes and platelets were measured. Statistics by t test (p<0.05) was done. There was a significant reduction in %ATI-g in kidney and blood (p<0.05) of splenectomized animals, a significant increase (p<0.05) of urea (88.8 ± 18.6 mg-dL) and creatinine (0.56 ± 0.08 mg-dL), compared to the controls (51.5±1.6, 0.37±0.02mg-dL, respectively), as well as increase in platelets and leucocytes, and hematocrit reduction. The analysis of the results indicates that in rats, splenectomy seems to alter the renal function and the uptake of 99mTc-DMSA

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

To evaluate the biodistribution of sodium pertecnetate (Na99mTcO4) 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 Na99mTcO4, 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 WizardTM 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 Na99mTcO4 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 Na99mTcO4 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

Biodistribuição do pertecnetato de sódio após desvio gástrico em Y de Roux (técnica de capella)

O desvio gástrico em Y de Roux é a técnica cirúrgica mais utilizada no tratamento da obesidade mórbida. Esta operação reduz o volume do estômago e o comprimento do intestino delgado, gerando alterações estruturais e metabólicas que podem influenciar no resultado de exames cintilográficos de pacientes operados. Com o objetivo de avaliar a biodistribuição pós-operatória do pertecnetato de sódio (Na99mTc) em órgãos de ratos Wistar submetidos à técnica do bypass (desvio) gástrico em Y de Roux (BGYR), foram utilizados 12 ratos distribuídos aleatoriamente em grupo tratado (n=6), submetido à cirurgia do BGYR e o grupo controle (C; n=6). No 15º dia de pós-operatório foi administrado 0,1 mL via plexo orbital de Na99mTc aos animais dos dois grupos, com atividade radioativa média de 0,66MBq. Após 30 minutos, os ratos foram mortos e retirados fragmentos de tireóide, coração, pulmão, fígado, estômago, rim e fêmur. As amostras foram lavadas com solução salina 0,9%, pesadas e submetidas ao Contador Gama 1470, WizardTM Perkin-Elmer-Finlândia para determinação do percentual de atividade radioativa total por grama (%ATI/g) de cada órgão. Empregou-se o teste t de Student para análise estatística, considerando-se significantes as diferenças das médias quando p<0,05. Redução significante na média de %ATI/g foi observada no fígado, estômago e fêmur dos animais submetidos à cirurgia de BGYR comparada ao grupo controle (p<0,05). Nos demais órgãos não houve diferença estatisticamente significativa entre os grupos. Em conclusão, a cirurgia BGYR em ratos modificou a biodistribuição do Na99mTc em alguns órgãos, podendo ter implicações clínicas na interpretação de exames cintilográficos. Este estudo xi teve um caráter multidisciplinar com a participação de pesquisadores das áreas de Cirurgia Experimental, Farmácia, Radiobiologia, Medicina Nuclear e Estatística

Influência da esplenectomia na biodistribuição do ácido dimercaptosuccínico-tecnécio-99m (99mTc-DMSA) em ratos Wistar

A esplenectomia é indicada em doenças hematológicas, hiperesplenismo grave, traumas e tem sido causa de importantes alterações metabólicas e imunológicas. O objetivo do presente trabalho é avaliar se a retirada do baço altera a biodistribuição do radiofármaco DMSA Tc99m em ratos Wistar e se há correlação com possíveis alterações da função renal. Foram usados dois grupos: esplenectomia (n=6) e controle (n=6) animais não operados. Após 15 dias, foi administrado 0,1 ml de DMSA-Tc99m via plexo orbital (0,66 MBq). Trinta minutos depois, foram retiradas amostras do rim, coração, pulmão, tireóide, estômago, bexiga, fêmur, sangue. Após pesadas as amostras, foi determinado o percentual de radioatividade/g (% ATI/g) em cada uma delas, com o Wizard Gama Counter Perkin-Elmer . Dosadas uréia e creatinina sérica, hematócrito, plaquetas e leucócitos. Estatística pelo teste t, com significância 0,05. Foi observada redução significante no %ATI/g no rim e sangue (p<0,05) dos animais esplenectomizados, aumento significante (p<0,05) da uréia (88,8±18,6mg/dL) e creatinina (0,56±0,08), comparado aos controles (51,5±1,6 e 0,37±0,02mg/dL, respectivamente) assim como leucocitose, aumento de plaquetas e redução de hematócrito. Em conclusão, a esplenectomia provocou comprometimento da função renal, repercutindo na alteração da captação de DMSA 99mTc pelo rim de ratos. Uma parceria entre a Unidade de Medicina Nuclear da Liga Norteriograndense Contra o Câncer e o Núcleo de Cirurgia Experimental da Universidade Federal do Rio Grande doNorte tornou possível a realização deste trabalho, que contou com a participação de profissionais de diferentes áreas como: Biologia, Biomedicina, Medicina Nuclear, Cirurgia Geral, Bioquímica e Estatística, atestando dessa forma o caráter multidisciplinar do trabalho

Effect of sildenafil in renal ischemia/reperfusion injury in rats

To evaluate the effect of sildenafil, administered prior to renal ischemia/reperfusion (I/R), by scintigraphy and histopathological evaluation in rats. Methods: Twenty-four rats were divided randomly into two groups. They received 0.1 ml of 99mTechnetium-etilenodicisteine intravenous, and a baseline (initial) renal scintigraphy was performed. The rats underwent 60 minutes of ischemia by left renal artery clamping. The right kidney was not manipulated. The sildenafil group (n=12) received orally 1 mg/kg of sildenafil suspension 60 minutes before ischemia. Treatment with saline 0.9% in the control group (n=12). Half of the rats was assessed after 24 hours and half after seven days I/R, with new renal scintigraphy to study differential function. After euthanasia, kidneys were removed and subjected to histopathological examination. For statistical evaluation, Student t and Mann-Whitney tests were used. Results: In the control group rats, the left kidneys had significant functional deficit, seven days after I/R, whose scintigraphic pattern was consistent with acute tubular necrosis, compared with the initial scintigraphy (p<0.05). Sildenafil treatment resulted in better differential function of the left kidneys 24h after reperfusion, compared with controls. Histopathologically, the left kidney of control rats (24 hours after I/R) showed a higher degree of cellular necrosis when compared with the sildenafil treated rats (p<0.05). Conclusion: Sildenafil had a protective effect in rat kidneys subjected to normothermic I/R, demonstrated by scintigraphy and histomorphometry

Influence of Splenectomy on the Biodistribution of Technetium-99m Dimercaptosuccinic Acid (99mTc-DMSA) in Rats

This study aimed to evaluate if the splenectomy alters the biodistribution of 99mTc-DMSA and renal function in Wistar rats. The animals were separated in the groups: splenectomy (n = 6) and control (n = 6). After splenectomy (15 days), the administration of 0.1ml of 99mTc-DMSA IV (0.48 MBq) was carried out. Thirty minutes later, kidney, heart, lung, thyroid, stomach, bladder and femur and samples of blood were isolated. The organs were weighed, counted and the percentage of radioactivity -g (%ATI-g) determined. Serum urea and creatinine, hematocrit, leukocytes and platelets were measured. Statistics by t test (p<0.05) was done. There was a significant reduction in %ATI-g in kidney and blood (p<0.05) of splenectomized animals, a significant increase (p<0.05) of urea (88.8 ± 18.6 mg-dL) and creatinine (0.56 ± 0.08 mg-dL), compared to the controls (51.5±1.6, 0.37±0.02mg-dL, respectively), as well as increase in platelets and leucocytes, and hematocrit reduction. The analysis of the results indicates that in rats, splenectomy seems to alter the renal function and the uptake of 99mTc-DMSA