Bed nucleus of the stria terminalis NMDA receptors and nitric oxide modulate contextual fear conditioning in rats

Author(s)

Hott, Sara C. ; Gomes, Felipe V. ; Uliana, Daniela L. ; Vale, Gabriel T. ; Tirapelli, Carlos R. ; Resstel, Leonardo B. M.

• Document type: Journal article
• Source: Neuropharmacology; v. 112, p. 9-pg., 2017-01-01.

Abstract

The bed nucleus of the stria terminalis (BNST) modulates anxiety-like responses, including conditioned emotional responses. Evidence suggests that glutamatergic neurotransmission in the BNST plays a role in the modulation of defensive responses. However, little is known about the involvement of glutamate NMDA receptor activation within the BNST, and its resultant increase in nitric oxide (NO) levels, in the expression of contextual fear conditioning (CFC). We investigated whether the antagonism of NMDA receptors or the reduction of NO levels in the BNST would attenuate behavioral and autonomic responses (i.e. increase in arterial pressure and heart rate, and decrease in tail cutaneous temperature) of rats submitted to a CFC paradigm. Intra-BNST infusion of AP7, an NMDA receptor antagonist, attenuated both behavioral and autonomic changes induced by CFC. Similar results were observed with NPLA and c-PTIO, an nNOS inhibitor and an NO scavenger, respectively. A positive correlation between BNST NO levels and the time spent in freezing behavior was also observed for animals submitted to the CFC. These findings indicate that the expression of CFC involves a facilitation of BNST NMDA receptor-NO signaling. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• FAPESP's process: 10/17343-0 - Evaluation of CBD effects on the molecular and behavioral changes induced by repeated treatment with MK-801
• Grantee: Felipe Villela Gomes
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 09/03187-9 - Involvement of rats medial prefrontal cortex on the aversive response observed in Vogel conflict test: a possible NMDA receptors, nitric oxide and endocannabinoid system pathway
• Grantee: Leonardo Resstel Barbosa Moraes
• Support Opportunities: Regular Research Grants
• FAPESP's process: 11/13299-9 - Bed nucleus of the stria terminalis noradrenergic system modulates contextual fear conditionig: possible interaction with CRF and glutamatergic neurotransmission
• Grantee: Sara Cristina Hott
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)