Chronic mild stress induces widespread decreases in thyroid hormone alpha1 receptor mRNA levels in brain--reversal by imipramine.

While considerable clinical evidence implicates thyroid hormones (THs) in depressive illness, the specific nature of this involvement remains unclear. The alpha1 subtype (TR-alpha1) is the most abundant TH receptor in brain. Here we investigated changes in TR-alpha1 mRNA in the chronic mild stress (CMS) model of depression.

Context fear conditioning inhibits panic-like behavior elicited by electrical stimulation of dorsal periaqueductal gray.

Context fear conditioning has been widely used as an animal model of anxiety whereas electrical stimulation of the dorsal portion of the periaqueductal gray (DPAG) as a model of panic attack. The present study employed these two animal models in order to investigate the influence of anxiety in the occurrence of panic attack. Results indicated that animals exposed to contextual cues that were previously associated with electrical footshocks engaged in robust defensive freezing behavior and were less likely to display flight evoked by electrical stimulation of the DPAG when compared with control animals that were not exposed to the context fear conditioning procedure.