Intellectual and scientific content of the study, protocol design, provision of guidelines for surgical intervention, supervision of all phases of the study, manuscript writing, critical revision. ABSTRACT PURPOSE:To evaluate the effects of vitamin K1 on wound healing in the left colon of rats with experimental biliary obstruction. METHODS:Sixteen male rats, divided into four groups of four animals each (L, M, LK, and MK), underwent colostomy followed by bowel suture in the left colon. Seven days before, animals in the L and LK groups had undergone common bile duct ligation. The animals in groups MK and LK received vitamin K1 supplementation. On day 7 after bowel suture, repeat laparotomy was performed for evaluation of colonic healing by burst pressure measurement and collection of samples for histopathological analysis. Changes in body weight were evaluated in the four groups. RESULTS:Weight loss was lower in animals supplemented with vitamin K. No significant differences were observed in burst pressure among the four groups (p>0.05). Histological analysis showed more hemorrhage and congestion in the biliary obstruction groups.Supplemented animals exhibited increased collagen formation and less edema and abscess formation. CONCLUSION:Vitamin K supplementation attenuated weight loss and improved colonic wound healing in rats.

PURPOSE:To evaluate the effects of pneumoperitoneum with carbon dioxide and helium on renal function and morphology in a rat model. METHODS:Twenty four rats were randomized into three groups (n=8): gasless insufflation ('open', Pressure=0 mmHg), carbon dioxide pneumoperitoneum at 12 mmHg, and helium pneumoperitoneum at 12 mmHg; all lasting 90 minutes.. A cystostomy was performed and the bladder was emptied. At the end of the experiment, the urine produced, a blood sample and the left kidney of each animal were collected. The following variables were obtained: serum sodium, potassium, urea and creatinine, urine volume and creatinine. The creatinine clearance was estimated for each animal. The kidneys were stained with hematoxylin and eosin (HE) and evaluated by a pathologist blinded to the groups. RESULTS:The CO 2 and Helium groups did not differ in the variables evaluated. Both developed oliguria (p<0.001 vs. gasless). The CO 2 group presented hyperkalemia compared to gasless (p=0.05), which did not attain significance in the helium group. Histopathological analysis revealed mild hydropic degeneration and congestion in the three groups, with no significant difference among them. CONCLUSIONS:The type of gas resulted in no difference in the variables of renal function and morphology assessed. The increase in serum potassium was only observed with CO 2 insufflation suggests a combined effect of elevated intra-abdominal pressure and metabolic effects of pneumoperitoneum.

Intellectual and scientific content of the study, designed the protocol, provided guidelines for the surgical interventions, supervised all phases of the study, manuscript writing, critical revision. ABSTRACT PURPOSE:To evaluate the influence of glutamine and obstructive jaundice on left colon healing in rats. METHODS:Sixteen male rats were allocated across four groups: LG -Common bile duct ligation followed by colotomy and bowel suture on postoperative day 7. Supplementation with glutamine 2% from day 4 after duct ligation until euthanasia. L -Common bile duct ligation followed by colotomy and bowel suture on postoperative day 7. No glutamine supplementation. M -Common bile duct manipulation followed by colotomy and bowel suture on postoperative day 7. No glutamine supplementation. MG -Common bile duct manipulation followed by colotomy and bowel suture on postoperative day 7. Supplementation with glutamine 2% from day 4 after duct manipulation until euthanasia. On the day of euthanasia, bursting pressure of the sutured bowel segment was measured and samples were collected for histopathological analysis. RESULTS:There were no differences in bursting pressure among groups : LG vs. M (110 ± 28 vs. 173 ± 12; p = 0.08). Groups L and MG were not different from group M (156 ± 12 and 118 ± 22. Glutamine supplementation was associated with less edema, polymorphonuclear lymphocyte infiltration, bacterial colonies, and abscess formation, as well as with increased collagen formation. CONCLUSION:Obstructive jaundice had no negative effect and glutamine supplementation had no positive effect on colonic scar strength in rats.