Marília Daniela Ferreira Carvalho

Metabolism and gastric remnant changes after Roux-en-Y gastric bypass in rats.

ABSTRACT Background: The Roux-en-Y gastric bypass (RYGB) may affect metabolism, microbiology, and histology of gastric remnant. Therefore, this study aimed to investigate these issues in rats. Methods: Twelve rats were randomly allocated to a RYGB group (n = 6) and nonoperated normal rats group (n = 6). After 30 postoperative days, all rats were injected with 0.1ml of Na99mTc− i.v. (radioactivity 0.66 MBq). After 30 min, liver, stomach, thyroid, heart, lung, kidney, and femur samples were harvested and weighed. Percentage radioactivity per gram of organ (%ATI/g) was determined using a Perkin-Elmer gamma counter. Serum albumin, calcium, aminotransferases (ALT, AST), T3, T4, and PTH were determined. Samples of the excluded stomach mucosa were harvested for bacterial and fungal count such as colony-forming units/g and histology. Results: A significant reduction (t test) in %ATI/g was observed in the liver, stomach, and femur in the RYGB rats, compared with normal rats (p < .05). A significant reduction in serum albumin and calcium in RYGB rats was detected, compared with normal rats (p < .05). ALT and AST were significantly different between the two groups. T3 and T4 levels were significantly lower in RYGB rats than in normal rats (p < .05); PTH levels were higher in RYGB rats than in controls (p = .009). The gastric remnant mucosa of RYGB rats showed higher bacterial and fungal count, atrophy, intestinal metaplasia, and neutrophilic polymorphonuclear inflammation than in normal rats. Conclusions: This investigation demonstrated that a model of murine RYGB significantly modified metabolic parameters and the microbiology/histology of the remnant stomach.

Metabolic and hematologic consequences of colectomy associated to hepatectomy in rats

PURPOSE To investigate the influence of partial colectomy associated with hepatectomy on the biodistribution of the (99m)Tc-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 30(th) postoperative day all rats were injected with (99m)Tc-phytate 0.1mL i.v. (radioactivity 0.66 MBq). After 15 minutes, liver sample was harvested and weighed. Percentage radioactivity per gram of tissue (%ATI/g) was determined using an automatic gamma-counter. Serum AST, ALT, alkaline phosphatase and red blood cells labeling were determined. RESULTS The liver %ATI/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.

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

PURPOSE 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.

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

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.

Ileal Interposition and Viability of Pancreatic Islets Transplanted into Intramuscular Site of Diabetic Rats

ABSTRACT Background: Assuming that ileal stimulation by food may increase incretin secretion, we aimed to investigate whether ileal interposition obtains adequate pancreatic islet viability and function after intramuscular islet transplantation in diabetic rats. Methods: We investigated four groups of eight Wistar rats: ileal interposition + islet transplantation, islet transplantation, ileal interposition, and diabetic control. All rats were subjected to streptozotocin-induced diabetes. We used the C-peptide/glucose ratio and islet image to investigate beta cell mass, and plasma glucagon like peptide-1 (GLP-1) measure. Results: Ileal interposition was effective in preserving function and increasing islet mass in animals with islets transplanted into alginate microcapsules. The plasma GLP-1 level in the diabetic control rats was a basal concentration (4.1 ± 1.2 pM). GLP-1 level after ileal interposition + islet transplantation (12.3 ± 3.3 pM) was significantly higher (p < .05) than in the islet transplantation group (8.2 ± 2.4 pM) and ileal interposition group rats (7.6 ± 1.8 pM). Conclusions: Ileal interposition positively influenced beta cell viability after intramuscular transplantation of pancreatic islets in diabetic rats.

Diabetes and biodistribution of pertechnetate (Na99mTcO4) in rats

PPurpose:This study aimed to clarify if diabetes induced in rats changes the biodistribution of the radiopharmaceutical sodium pertechnetate (Na99mTcO4) and, consequently, the accuracy of the scintigraphic exams. Methods: We used 14 male Wistar rats, randomly allocated in 2 group: the diabetic group (D) rats (n=7) were submitted to the induction of diabetes with streptozotocin, and 7 non diabetic rats were used as controls (C). After 7 days, in the 14 animals it was administered 0,1 mL of Na99mTcO4 (0.66 MBq) through orbital plexus and, after 30 minutes, the radiopharmaceutical sodium pertechnetate was evaluated, being compared the uptske of this in the several studied organs of diabetic animals and controls.Results: The biodistribution of Na99mTcO4 was significantly higher in the liver and smaller in the bladder, thyroid and stomach of diabetic mice when compared to the control group rats. Conclusion: Diabetes induced in rats alters the biodistribution of Na99mTcO4, and this finding could have clinical implications on scintigraphic exams.

P76 Computerized cardiotocography in fetuses with central nervous system abnormalities

age of 36–40 weeks (n =25), respectively: mean basal FHR (143.6±5.2 bpm vs. 134.2±13.8bpm, p =0.04), mean number of FHR accelerations >10 bpm (4.3±2.1 vs. 8.2±4.6, p = 0.01), mean number of FHR accelerations >15 bpm (1.0±0.8 vs. 5.2±3.7, p = 0.001), mean high variation episodes duration (8.5±7.8min vs. 14.9±8.5min, p = 0.04), and mean short term variation (7.7±1.9 vs. 10.6±4.2, p = 0.03). Conclusion: This study suggests that there are differences in the computerized cardiotocography parameters in normal pregnancies of 36–40 weeks compared to pregnancies of 24–26 weeks’ gestation, showing immaturity of central nervous system.