Validation of protocol of experimental necrotizing enterocolitis in rats and the pitfalls during the procedure

Author(s)

Lanhellas Goncalves, Frances Lilian ^[1] ; Gallindo, Rodrigo Melo ^[1] ; Mangueira Soares, Lucas Manoel ^[1] ; Figueira, Rebeca Lopes ^[1] ; Perecim Volpe, Fabio Antonio ^[1] ; Pereira-da-Silva, Maurcio Andre ^[1] ; Sbragia, Lourenco ^[1]

Affiliation

^[1] Univ Sao Paulo FMRP USP, Sch Med Ribeirao Preto, Dept Surg & Anat, Div Pediat Surg, Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: Acta Cirurgica Brasileira; v. 28, n. 1, p. 19-25, 2013.
• Web of Science Citations: 2

Abstract

PURPOSE: To describe the difficulties of implementing the protocol of experimental necrotizing enterocolitis (NEC) in order to obtain a larger number of newborns affected with the disease and a lower mortality. METHODS: Term Sprague-Dawley newborns rats (22 days) were divided into four groups of 12 fetuses each (n = 48): EC - breastfed newborns; IH - breastfed newborns and subjected to a stress protocol by ischemia and hypothermia; ESB - formula-fed newborns (Esbilac (R), PetAg, Hampshire, IL, USA) and NEC - formula-fed newborns and subjected to stress protocol. The parameters set for the study protocol were: milk concentration (0.19 g ml or 0.34 g/ml), diet instilled volume (according to body weight - 200 kcal/day/Kg - or progressive, according to acceptance), weight (gain, loss or maintenance) and duration of the experiment (72 hours or 96 hours). Data of body weight (BW), intestinal weight (IW) and the IW/BW ratio were obtained. Samples of terminal ileum were collected and analyzed by the degree of injury to the intestinal wall. Statistically significance was set to p<0.05. RESULTS: The established protocol with less mortality and increased number of NEC was with Esbilac (R) at a concentration of 0.19 g/ml of diet instilled volume of 0.1 ml, every 3 hours, for 72 hours. All infants fed with artificial milk lost weight. In the degree score of intestinal injury, the ESB, IH and NEC groups were considered positive for NEC with greater histological injury in the latter. CONCLUSION: The described NEC protocol in rats allowed a greater survival of puppies with a greater number of animals affected by the disease. (AU)

• FAPESP's process: 11/12587-0 - Evaluation in vivo of the effect of corticosteroids and ventilation in oxide nitric pathway on the expression of VEGF and its pulmonary receptors after fetal tracheal occlusion in the congenital diaphragmatic hernia in rats
• Grantee: Frances Lilian Lanhellas Gonçalves
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 11/00794-1 - Assessment of nitric oxide (NO) in vivo after fetal tracheal occlusion on the expression of VEGF receptors in pulmonary congenital diaphragmatic hernia induced by Nitrofen
• Grantee: Lourenço Sbragia Neto
• Support Opportunities: Regular Research Grants