"Involvement of TRPV1 receptors and glutamtergic and nitrergic neurons located in the dorsolateral periaquedcutal grey on defensive reactions in rats"

• Grant number: 08/03177-0
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2008
• End date: February 28, 2010
• Field of knowledge: Biological Sciences - Pharmacology - Neuropsychopharmacology
• Principal Investigator: Francisco Silveira Guimaraes
• Grantee: Daniele Cristina de Aguiar
• Host Institution: Faculdade de Medicina de Ribeirão Preto (FMRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 07/03685-3 - Typical and atypical neurotransmitters in neuropsychiatric disorders, AP.TEM

Abstract

Several pieces of evidence indicate that glutamate- and nitric oxide-mediated neurotransmission facilitate defensive responses coordinated by the dorsolateral periaqueductal gray (dlPAG). In addition, other neurotransmitters present in the dlPAG could also modulate these responses, including the endovanilloids. Activation of vanilloid TRPV1 receptors facilitates glutamatergic neurotransmission in the dlPAG but their role in defensive responses remains poorly studied. The present project is aimed at investigating a possible interaction among glutamate, nitric oxide and vanilloid-mediated neurotransmission in the dlPAG on the control of these responses. We will verify if dlPAG TRPV1 receptors are involved in the defensive reactions displayed by rats when confronted with a live predator (cat) or induced by local administration of glutamate agonist or NO donor. In addition to the pharmacological studies, we will investigate if neurons that contain TRPV1 receptors are activated by cat exposure and if these and other activated neurons by this stimulus are glutamatergic or contain the enzyme nitric oxide synthase.