Involvement of platelets in the genesis of inflammatory pain: study of chemical and cell mediation

• Grant number: 12/24621-1
• Support Opportunities: Regular Research Grants
• Start date: April 01, 2013
• End date: March 31, 2015
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Renata Giorgi
• Grantee: Renata Giorgi
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil

Abstract

Platelets are small blood cells known for their importance in the process of hemostasis and tissue repair. The role and importance of these cells in the inflammatory process have been revealed, but paucity of information is available about the involvement of platelets in pain genesis. Recent studies developed by our group demonstrated that depletion of platelets in mice inhibited hyperalgesia induced by carrageenan and Bothrops jararaca venom. In addition, intraplantar injection of washed whole rat platelets (200 × 109 platelets / L) or platelet releasate has been shown to result mechanical hyperalgesia. in rats submitted to the paw pressure model. These data suggest that platelets and their granular content are extremely important in the genesis of inflammatory hyperalgesia. However, the mechanisms underlying this phenomenon have not yet been investigated. Based on such information, this project aims to determine the mechanism of molecular and cellular mediation involved in the hyperalgesia induced by the platelet releasate in rats, which will be evaluated by the paw pressure model. Diverse pharmacological and biochemical treatments, as well as histological analyzes, will be used to investigate possible mediators involved in hyperalgesia. Moreover, the participation of neutrophils and circulating platelets in this effect will also be evaluated. The results will help to understand the involvement of platelets in the genesis of inflammatory pain, besides providing novel therapeutic approaches for the treatment of pain associated with hemostatic disorders. (AU)