The µ-opioid system in midline thalamic nuclei modulates defence strategies towards a conditioned fear stimulus in male mice.

ABSTRACT:

Background

Nuclei located in the dorsal midline thalamus, such as the paraventricular nucleus of the thalamus (PVT), are crucial to modulate fear and aversive behaviour. In addition, the PVT shows a dense expression of µ-opioid receptors (MORs) and could mediate the anxiolytic effects of opioids.

Methods

We analysed the contribution of MORs in the dorsal midline thalamus (i.e. the PVT) to the performance of mice in a classical fear conditioning paradigm. We locally injected a specific agonist (DAMGO), an antagonist (CTAP) of MOR or saline as a control into the dorsal midline thalamus of male mice, prior to fear extinction training. We assessed freezing as a typical measure of fear and extended our analysis by evaluation of aversive, non-aversive and neutral behavioural featu

SUBMITTER: Bengoetxea X 

PROVIDER: S-EPMC7604929 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature