title: Action of tacrolimus on Wistar rat kidneys implanted with Walker 256 carcinosarcoma.
abstract: OBJECTIVE
  To evaluate the development of Walker 256 tumor in male Wistar rats treated with tacrolimus using an experimental kidney tumor model.
  
  
  METHODS
  40 male Wistar rats were divided into four groups: Tumor group (TU) (n=10), Tacrolimus-Tumor group (TT) (n=10), Tacrolimus group (TC) (n=10) and Control group (C) (n=10). Treatment with tacrolimus was performed in groups TT and TC. Under anesthesia, the right kidney of each animal of TU and TT was accessed through a supraumbilical incision and inoculated with a 0.1 mL solution containing 2 x 10(6) tumor cells (Walker 256 carcinosarcoma tumor cells). Group TC was treated with a saline solution. All the animals of groups TC and TT were treated with tacrolimus (5mg/kg/day) by gavage for 15 days. TU group animals received saline by gavage for 15 days. On the 15th postoperative day, all animals were submitted to euthanasia and blood sampling for analysis of serum creatinine (Cr) and blood urea nitrogen (BUN). Abdominal gross examination was performed, the right kidney removed and prepared for histological analysis by hematoxylin-eosin staining. The resulting data were submitted to statistical analysis by ANOVA.
  
  
  RESULTS
  Statistical significance was found when comparing creatinine level between groups TU, TT and TC -TT group culminated with a marked increased in creatinine levels (Cr=1.013 + or - 0.3028 mg/mL), TU group (Cr=0.5670 + or - 0.03536 mg/dL) P=0.00256, TC group (Cr =0.711 + or - 0.1653 mg/mL) P= 0.02832. Statistical significance was found when comparing BUN levels in TT group (71.32 + or - 17.14 mg/mL), compared with TU group (45.83 + or - 5.046 mg/dL), P=0.000318. There were no statistically significant differences between groups TT and TC (61.23 + or - 9.503 mg/mL) P=0.7242. Histological analysis showed a poor evolution in TT group with multiple foci of hemorrhage and cortical invasion by the Walker tumor.
  
  
  CONCLUSIONS
  The Tacrolimus-treated group developed a more aggressive tumor and a drug-related nephrotoxic effect.
authors.affiliation: Evangelic Faculty of Parana, University Evangelic Hospital, Curitiba, PR, Brazil. ipem@evangelico.org.br
authors.forename: Cristiano Machado
authors.initials: CM
authors.lastname: Inácio
authors.forename: Ulrich Andréas
authors.initials: UA
authors.lastname: Dietz
authors.forename: Osvaldo
authors.initials: O
authors.lastname: Malafaia
authors.forename: Jurandir Marcondes
authors.initials: JM
authors.lastname: Ribas Filho
authors.forename: Paulo Afonso Nunes
authors.initials: PA
authors.lastname: Nassif
authors.forename: Nicolau Gregori
authors.initials: NG
authors.lastname: Czeczko
authors.forename: Carmen Australia Paredes
authors.initials: CA
authors.lastname: Marcondes
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001806:Blood Urea Nitrogen; D002279:Carcinoma 256, Walker / Q000473:pathology*; D003401:Creatine / Q000097:blood; D004195:Disease Models, Animal; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007668:Kidney / Q000187:drug effects* / Q000473:pathology; D007680:Kidney Neoplasms / Q000473:pathology*; D016030:Kidney Transplantation; D008297:Male; D009368:Neoplasm Transplantation; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D016559:Tacrolimus / Q000627:therapeutic use*
chemical_list: D007166:Immunosuppressive Agents; D003401:Creatine; D016559:Tacrolimus