Abstract
The present experiments were designed to study fear conditioning as an emotional learning task with disrupted visceral feedback. For that purpose we used the peripherally acting β1-adrenoceptor blocker atenolol and studied its effects on the behavior of male C57BL/6JOlaHsd mice in an exploration-related test and during fear-conditioning. In the first experiment, we treated mice with saline or different doses of the β1-adrenergic blocker atenolol (5 mg/kg and 20 mg/kg body weight i.p.) 30 min before behavioral testing in a motility box. Only the high but not the low dose of atenolol led to a reduction of locomotor activity (p <0.02). Factors known to be related to emotionality (rearing, area preference) were unaffected. In a second experiment, saline- and atenolol-treated mice (same dosages and mode of application) were trained for auditory fear conditioning, and 24 h later they were retested in the same environment. We found differences between the effects of atenolol upon contextual- and cue-fear conditioning. Animals treated with 20 mg/kg BW doses of atenolol showed significantly decreased background contextual fear compared to saline-treated control animals. In contrast, no differences were found during CS presentation in the conditioning context between atenolol-treated animals and saline-treated controls, independent from a paired or an unpaired conditioning paradigm. Thus, the blockade of peripheral β1-adrenoceptors by atenolol may have disrupted the positive feedback to the central nervous system via visceral afferents resulting in a decreased locomotor activity and background contextual fear.
| Original language | English |
|---|---|
| Pages (from-to) | 109-118 |
| Number of pages | 10 |
| Journal | Behavioural Brain Research |
| Volume | 182 |
| Issue number | 1 |
| DOIs | |
| State | Published - Aug 22 2007 |
| Externally published | Yes |
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All Science Journal Classification (ASJC) codes
- Behavioral Neuroscience
Cite this
Disrupted visceral feedback reduces locomotor activity and influences background contextual fear conditioning in C57BL/6JOlaHsd mice. / Janitzky, K.; Linke, R.; Yilmazer-Hanke, D. M.; Grecksch, G.; Schwegler, H.
In: Behavioural Brain Research, Vol. 182, No. 1, 22.08.2007, p. 109-118.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Disrupted visceral feedback reduces locomotor activity and influences background contextual fear conditioning in C57BL/6JOlaHsd mice
AU - Janitzky, K.
AU - Linke, R.
AU - Yilmazer-Hanke, D. M.
AU - Grecksch, G.
AU - Schwegler, H.
PY - 2007/8/22
Y1 - 2007/8/22
N2 - The present experiments were designed to study fear conditioning as an emotional learning task with disrupted visceral feedback. For that purpose we used the peripherally acting β1-adrenoceptor blocker atenolol and studied its effects on the behavior of male C57BL/6JOlaHsd mice in an exploration-related test and during fear-conditioning. In the first experiment, we treated mice with saline or different doses of the β1-adrenergic blocker atenolol (5 mg/kg and 20 mg/kg body weight i.p.) 30 min before behavioral testing in a motility box. Only the high but not the low dose of atenolol led to a reduction of locomotor activity (p <0.02). Factors known to be related to emotionality (rearing, area preference) were unaffected. In a second experiment, saline- and atenolol-treated mice (same dosages and mode of application) were trained for auditory fear conditioning, and 24 h later they were retested in the same environment. We found differences between the effects of atenolol upon contextual- and cue-fear conditioning. Animals treated with 20 mg/kg BW doses of atenolol showed significantly decreased background contextual fear compared to saline-treated control animals. In contrast, no differences were found during CS presentation in the conditioning context between atenolol-treated animals and saline-treated controls, independent from a paired or an unpaired conditioning paradigm. Thus, the blockade of peripheral β1-adrenoceptors by atenolol may have disrupted the positive feedback to the central nervous system via visceral afferents resulting in a decreased locomotor activity and background contextual fear.
AB - The present experiments were designed to study fear conditioning as an emotional learning task with disrupted visceral feedback. For that purpose we used the peripherally acting β1-adrenoceptor blocker atenolol and studied its effects on the behavior of male C57BL/6JOlaHsd mice in an exploration-related test and during fear-conditioning. In the first experiment, we treated mice with saline or different doses of the β1-adrenergic blocker atenolol (5 mg/kg and 20 mg/kg body weight i.p.) 30 min before behavioral testing in a motility box. Only the high but not the low dose of atenolol led to a reduction of locomotor activity (p <0.02). Factors known to be related to emotionality (rearing, area preference) were unaffected. In a second experiment, saline- and atenolol-treated mice (same dosages and mode of application) were trained for auditory fear conditioning, and 24 h later they were retested in the same environment. We found differences between the effects of atenolol upon contextual- and cue-fear conditioning. Animals treated with 20 mg/kg BW doses of atenolol showed significantly decreased background contextual fear compared to saline-treated control animals. In contrast, no differences were found during CS presentation in the conditioning context between atenolol-treated animals and saline-treated controls, independent from a paired or an unpaired conditioning paradigm. Thus, the blockade of peripheral β1-adrenoceptors by atenolol may have disrupted the positive feedback to the central nervous system via visceral afferents resulting in a decreased locomotor activity and background contextual fear.
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UR - http://www.scopus.com/inward/citedby.url?scp=34447252766&partnerID=8YFLogxK
U2 - 10.1016/j.bbr.2007.05.015
DO - 10.1016/j.bbr.2007.05.015
M3 - Article
VL - 182
SP - 109
EP - 118
JO - Behavioural Brain Research
JF - Behavioural Brain Research
SN - 0166-4328
IS - 1
ER -