Anatomo-radiological correlation using 18-FDG-PET in abdominal sepsis model in rats. A preliminary study

Abstract Purpose: To examine a correlation of micro-PET images with photographic images of the digestive organs in abdominal sepsis model. Methods: Male Wistar rats weighing 265±18g were used. Abdominal sepsis was induced by ligature and cecal puncture. Micro-PET Images from abdominal cavity septic foci were obtained using 18-Fluoro-deoxyglucose, looking for a correlation with photographic images of abdominal cavity organs. Pearson's correlation test was used. Results: The mean standard uptake values (SUV) and lesion areas were 2.58±0.63SUVbwg/ml and 546.87±300.95mm2, respectively. There was a strong positive correlation between the two variables (r=0.863, p=0.137), which resulted in a coefficient of determination r2?0.75, meaning that 75% of SUV variation is explained by the lesion areas of digestive organs. Conclusion: Micro-PET allows high throughput assessment of lesion count and volume in pre-clinical rat model of CPL abdominal sepsis.

The renoprotective effect of oral Tadalafil pretreatment on ischemia/reperfusion injury in rats

Abstract Purpose: To evaluate the effect of tadalafil in renal ischemia/reperfusion (I/R) injury in rats Methods: Group I/R saline rats (n=6) were subjected to 45 minutes of left renal ischemia and treated with saline; the I/R tadalafil rats (n=6) received oral 10mg/kg tadalafil microemulsion one hour before ischemia. In both groups, 8 hours after ischemia, laboratory analysis were performed Results: Better tissue perfusion was lower in ischemic left/kidney than in right/kidney in saline group, suggesting reduced kidney clearance. Fluorescence in left/kidneys of tadalafil treated rats was lower than in right/kidneys (difference not significant). The fluorescence signal intensity in kidneys of tadafil treated rats was higher than in saline rats. TNF-α levels were significantly lower in I/R tadalafil group rats compared to I/R saline group (154±10.3 vs 391.3±12.3), as well as IL-1β (163.4±13.2 vs 279±11.5pg/dL), and IL-6 (122.9±8.1 vs 173.7±6.3 respectively; p=0.0001). Urea, creatinine and C-reactive protein were significantly lower in tadafil treated rats then in saline group Conclusion: Tadalafil therapy decreased the expression of circulating pro-inflammatory cytokines in a renal I/R rodent model, while improving kidney function proofs.

Effects of cococonut water and simvastatin in the treatment of sepsis and hemorrhagic shock in rats

ABSTRACT PURPOSE: To evaluate the effects of modified coconut water as fluid of resuscitation combined with simvastatin in hemorrhagic shock and sepsis model in rats. METHODS: Four groups of Wistar rats with hemorrhagic shock and abdominal sepsis were studied (n=8/group). Rats were bled and maintained at a mean blood pressure 35mmHg for 60min. They were then resuscitated with: 1) saline 0.9%; 2) coconut water+3% NaCl; 3) coconut water+NaCl 3%+simvastatin microemulsion (10 mg/kg i.v.; 4) normal coconut water. At 8h post-resuscitation, blood and lungs were collected for exams. RESULTS: Clinical scores, TNF-α, IL-1β, liver/kidney proof levels, and lung injury were significantly reduced in coconut water+NaCl 3%+simvastatin group treated rats, comparing with the other resuscitation treatments. CONCLUSIONS: Resuscitation with coconut water with Nacl 3%+simvastatin had a significant beneficial effect on downregulating cytokines and decreasing lung injury in a rat model of abdominal sepsis and hemorrhagic shock. We also demonstrated that coconut water with Nacl 3%+simvastatin administration clearly made liver and kidney function better and improved clinical score.

Heart and systemic effects of statin pretreatment in a rat model of abdominal sepsis. Assessment by Tc99m-sestamibi biodistribition

PURPOSE: To evaluate the heart and the Tc-99m-sestamibi biodistribution after statin pretreatment in a rat model of abdominal sepsis. METHODS: Twenty-four Wistar rats were randomly distributed into four groups (n=6 per group): 1) sepsis with simvastatin treatment, 2) sepsis with vehicle, 3) sham control with simvastatin and 4) sham control with vehicle. 24 hours after cecal ligation and puncture rats received 1.0MBq of Tc-99m-sestamibi i.v. 30min after, animals were euthanized for ex-vivo tissue counting and myocardium histological analysis. RESULTS: Myocardial histologic alterations were not detected 24 hours post-sepsis. There was significantly increased cardiac Tc-99m-sestamibi activity in the sepsis group with simvastatin treatment (1.9±0.3%ID/g, p<0.001) in comparison to the sepsis group+vehicle (1.0±0.2%ID/g), control sham group+ simvastatin (1.2±0.3%ID/g) and control sham group (1.3±0.2%ID/g). Significant Tc-99m-sestamibi activity in liver, kidney and lungs was also detected in the sepsis group treated with simvastatinin comparison to the other groups. CONCLUSIONS: Statin treatment altered the biodistribution of Tc-99m-sestamibi with increased cardiac and solid organ activity in rats with abdominal sepsis, while no impact on controls. Increased myocardial tracer activity may be a result of a possible protection effect due to increased tissue perfusion mediated by statins. .

The ileum positively regulates hepatic regeneration in rats

To test the hypothesis that liver regeneration after partial hepatectomy can be influenced by the ileum. METHODS: Eighteen Wistar rats were distributed into groups of six animals: 1 - ileum resection+ hepatectomy 2/3; 2 - hepatectomy 2/3, and 3 - sham. Anesthesia with ketamine and xylazine i.p., aseptic technique, analgesia with meperidine (10mg/kg s.c.). On day 6, serum ALT, AST, alkaline phosphatase (AP) and albumin were measured. Liver regeneration and hepatocyte mitosis were quantified. Statistical analysis with ANOVA and Tukey tests, with significance p<0.05. RESULTS: In group hepatectomy+ileal resection, ALT, AST and AP were 180.6±24.9, 58.6±3.1 and 254.6±46.6 respectively. They were significantly higher than in the hepatectomy group, whose values were 126.0±16.5, 44.1±3.9 and 163.5±8.6, respectively (p<0.001). Albumin levels were not significantly different among groups. Liver regeneration in hepatectomy group (94.17%) was statistically higher (p<0.001) than in ileal resection+hepatectomy group (55.96%). In the latter group the mitosis of hepatocytes were significantly less frequent than in the hepatectomy group. CONCLUSION: The data confirm that the ileum positively influence on liver regeneration in rats undergoing hepatectomy.

Metabolic and hematologic consequences of colectomy associated to hepatectomy in rats / Consequências metabólicas e hematológicas da colectomia associada à hepatectomia em ratos

PURPOSE: To investigate the influence of partial colectomy associated with hepatectomy on the biodistribution of the 99mTc-phytate, on metabolic parameters, as well as labeling and morphology of red blood cells. METHODS: Wistar rats were distributed into three groups (each with six), nominated as colectomy, colectomy+hepatectomy and sham. In the 30th postoperative day all rats were injected with 99mTc-phytate 0.1mL i.v. (radioactivity 0.66 MBq). After 15 minutes, liver sample was harvested and weighed. Percentage radioactivity per gram of tissue ( percentATI/g) was determined using an automatic gamma-counter. Serum AST, ALT, alkaline phosphatase and red blood cells labeling were determined. RESULTS: The liver percentATI/g and red blood cells labeling were lower in colectomy and colectomy+hepatectomy rats than in sham rats (p <0.05), and no difference was detected comparing the colectomy and colectomy+hepatectomy groups. Red blood cells morphology did not differ among groups. Serum levels of AST, ALT and alkaline fosfatase were significantly higher in colectomy+hepatectomy than in colectomy rats (p<0.001). CONCLUSION: Hepatectomy associated with colectomy lowered the uptake of radiopharmaceutical in liver and in red blood cells in rats, coinciding with changes in liver enzymatic activity.

OBJETIVO: Investigar a influência da colectomia associada à hepatectomia parcial, na biodistribuição do fitato-99mTcO4, na marcação e morfologia de hemácias e em parâmetros metabólicos. MÉTODOS: Ratos Wistar foram distribuídos em três grupos (seis animais cada), denominados: colectomia, colectomia+hepatectomia e sham. No 30º dia pós-operatório, em todos eles foi feita injeção de 0,1 mL i.v. de fitato-99mTcO4 (radioatividade 0,66 MBq). Após 15 minutos, uma amostra de fígado foi colhida e pesada. O percentual de radioatividade por grama de tecido ( por centoATI/g) foi determinado no fígado e hemácias usando-se um contador gama automático. Dosagem sérica de AST, ALT, fosfatase alcalina, morfologia e marcação de hemácias com pertecnetato foram determinadas. RESULTADOS: O por centoATI/g no fígado e nas hemácias foi menor nos animais dos grupos colectomia e colectomia+hepatectomia do que no grupo sham (p<0,05; teste de Tukey). Nenhuma diferença foi detectada comparando os grupos colectomia e colectomia+hepatectomia. A morfologia das hemácias não diferiu entre os três grupos. Os níveis séricos de AST, ALT e fosfatase alcalina foram significativamente maiores no grupo colectomia+hepatectomia do que no grupo colectomia (p<0,001). CONCLUSÃO: A colectomia associada a hepatectomia contribuiu para reduzir a captação de radiofármaco no fígado e hemácias de ratos, coincidindo com alterações na atividade enzimática do fígado.