Conditioned defensive burying: A new paradigm for the study of anxiolytic agents

Abstract

Behavioral paradigms that have been designed to mimic forms of learning that are important for the survival of animals in the wild, rather than to minimize the contributions of adaptive predispositions, may prove to be particularly useful for studying the behavioral effects of drugs. In the present experiments, the propensity of rats to bury sources of aversive stimulation was disrupted in a dose-dependent fashion by a single injection of the anxiolytic drug, diazepam. This suggested that the conditioned defensive burying paradigm could prove to be a valuable addition to the paradigms available for studying anxiolytic effects. Supporting this view were two additional observations. First, the relative potencies of diazepam, chlordiazepoxide, and pentobarbital in the burying paradigm compared favorably with their relative potencies in clinical settings. Second, the effects of anxiolytics on conditioned burying appeared to be dissociable from the effects of other drugs that disrupt this behavior.

Differential blockade of CRF-evoked behaviors by depletion of norepinephrine and serotonin in rats

“…The LC is a major target of CRF neurotransmission in the brain (Van Bockstaele et al 1996) and is positioned to influence the functioning of the entire nervous system though modulation of noradrenergic activity (Abercrombie and Jacobs In agreement with its attenuation of burying responses to CRF administration, DSP-4 pretreatment also decreased the duration of probe burying in the conditioned defensive burying test, which is considered a validated rat test of anxiety (Treit et al 1981). No differences in the latency to contact the probe were observed between DSP-4-treated and control animals, indicating that the attenuation of burying was not due to an overall decrease in locomotion or exploratory activity.…”

“…This commonly-used behavioral test of anxiety measures burying behavior in rats that is directed towards an electrified probe (Treit et al 1981). As shown in Figure 7, DSP-4 pretreatment produced a significant decrease in time spent burying the shockprobe (t(17) = 2.77, p = 0.01).…”

“…Rodent burying behavior has long been described as a defensive coping strategy in natural habitats (Calhoun 1962;MacClintock 1970;Owings and Coss 1977). Furthermore, in the context of defensive avoidance, this proactive form of stress management provides an index of anxiety when directed at an electrified probe (Bondi et al 2007;De Boer et al 1990;Korte et al 1992;Treit et al 1981), and is enhanced and attenuated by anxiogenic and anxiolytic drugs, respectively (De Boer and Koolhaas 2003;Diamant et al 1992). To the best of our knowledge, the present studies are the first to specifically characterize and quantify the burying response to i.c.v.…”

Resolving the neural circuits of anxiety

“…Rodents will bury an electrified probe following conditioning in which they receive shocks from the probe 43 , and will even spontaneously bury novel marbles introduced into their home cages 44 . This burying behavior is quantifiable and sensitive to anxiolytics 45,46 . Hyponeophagia (novelty suppressed feeding) has also been used to assess anxiety-like behavior in rodents; in a novel environment, hungry mice exhibit an increased latency to feed that is sensitive to BZDs and SSRIs 47,48 .…”

Fluoxetine Disrupts the Integration of Anxiety and Aversive Memories

“…In this test, rats shocked from a stationary, electrified probe push bedding material from the floor of the experimental chamber toward the shock-probe (ie they bury the probe), avoid further contacts with the probe, and exhibit freezing behavior (Treit et al, 1994(Treit et al, , 1981Frye and Seliga, 2003;Pinel and Treit, 1978). In rats it has been demonstrated that anxiolytic drugs such as diazepam decrease burying towards the shock-probe (de Boer et al, 1990;Treit et al, 1993;Tsuda et al, 1988), whereas anxiogenic drugs such as yohimbine increase shock-probe burying (Tsuda et al, 1988).…”