Panic-like behaviors in Carioca high-and low-conditioned freezing rats.

Abstract

Panic disorder involves both recurrent unexpected panic attacks and persistent concern about having additional attacks. Electrical stimulation of the dorsal periaqueductal gray (dPAG) is an animal model of both panic attack and panic disorder, whereas contextual fear conditioning represents a model of anticipatory anxiety. Previous research indicated that anxiety has an inhibitory effect on panic attack-like behavior. However, still unclear is the role that anticipatory anxiety plays in panic disorder-like behaviors. This issue was investigated with two lines of animals selectively bred for high (Carioca High-Freezing) and low (Carioca Low-Freezing) freezing in response to contextual cues associated with footshock. The results suggest that although anticipatory anxiety might exert an inhibitory effect on the expression of panic attack, it might also facilitate the pathogenesis of panic disorder.

Endocrine and metabolic function in male Carioca High-conditioned Freezing rats

“…This defensive freezing response has been shown to be an important animal model of anxiety disorders [7]. The CHF line was validated behaviorally by tests used in other animal model of anxiety, including the elevated plus maze, the social interaction test, and defensive responses induced by electrical stimulation of the dorsal periaqueductal gray [11,16,20,21]. In the present study we evaluated the relationship between sustained elevated corticosterone serum levels and development of metabolic dysfunctions in the CHF line.…”

Psychobiological Aspects of Panic Disorder

“…Conversely, clinical trials with the 5-HT 2A/2C receptor antagonist ritanserin reduced symptoms of anticipatory anxiety [31] but exacerbated the incidence of panic attacks [32]. Finally, experimental studies that used animal models of anxiety supported the view that the activation of neural circuitry that is involved in anxiety might, in fact, inhibit the incidence of panic attacks [33,34,35].…”

Distinct patterns of brain Fos expression in Carioca High- and Low-conditioned Freezing Rats

“…Several rodent models have been developed to investigate the possible etiological mechanisms that underlie anxiety disorders [6][7][8][9]. Among these, fear conditioning in response to contextual cues is a well-studied experimental model of the aversive expectations of danger that are observed in patients suffering from generalized anxiety disorder [10,11]. Furthermore, considerable evidence indicates that contextual fear conditioning in rats involves neural circuitries similar to that associated with anxiety disorders in humans [12][13][14].…”