Analysis of the participation of leukotrienes in LPS-induced tolerance in the rat periodontium

• Grant number: 08/07078-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2008
• End date: October 31, 2009
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Maria José Alves da Rocha
• Grantee: Erick Ricardo Silva
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

In the begin of the periodontitis or in the acute periodontitis can occur increase of body temperature (Tb), however this increase does not persist in the chronic periodontitis. Recent studies of our group have mimic the clinical course of a periodontitis in animals through the repeated LPS injections in the rat periodontium. The results show that an increase in TB during the acute phase, but a tolerance after the repeated LPS injections. The objective of this work is to analyse the mechanism of this tolerance. Wistar rats weighing 250-300g will have the lateral ventricle cannulated by stereotaxia and datalogger implanted in the peritoneal cavity previously programmed for the begin of the Tb measurement. The animal will be left to recover for 5 and 7 days. One day before the experiment a catheter will be placed in the animal periodontium. In the day of experiment the animals will be divided in two groups. In one group, 2ul of MK-886 (1ug/kg) will be injected i.c.v. 30 minutes before of the injection of 3ul of LPS (10ug/kg) through the gingival catheter. In the outher group the same dose of MK-886 (1ug/kg) will be injected i.c.v. wiht the difference that the gingival injection will be saline instead LPS. The controls will be injected with DMSO 5% i.c.v. The variation of TB will be measured in 15 minutes intervals, during a period of 1h before and 7h after the treatments. (AU)