کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9149790 1166437 2005 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of apomorphine on rat behavior in the elevated plus-maze
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی فیزیولوژی
پیش نمایش صفحه اول مقاله
Effects of apomorphine on rat behavior in the elevated plus-maze
چکیده انگلیسی
It has been reported that novelty may evoke both an exploratory and a fear drive, thus generating behavior responding to an approach/avoidance conflict. However, not much is known about the approach component. Whereas there exists abundant evidence referring to the avoidance component as the main target for the anxiolytic action of benzodiazepines, the involvement of dopaminergic mechanisms in fear and anxiety is controversial. The present study examined the effects of the dopaminergic agonist apomorphine, the D2 dopaminergic antagonist sulpiride and the combined treatment sulpiride plus apomorphine on conventional and non-conventional measures of the behavior of rats exposed to an elevated plus-maze. Systemic injection of apomorphine (0.25, 0.5 and 1.0 mg/kg) caused a selective increase in the time spent in the open arms and in the open arm extremities. Pre-treatment with sulpiride blocked these effects while this dopaminergic antagonist had no effect by its own. Apomorphine produced no significant effects on stretching, flat-back-approach or scanning. Therefore, apomorphine increased the behavioral response linked to the approach component of the conflict without affecting risk assessment behaviors. These findings suggest that dopaminergic mechanisms, probably through D2 receptors, may also be involved in the mediation of the conflict derived from the need of gathering information for confirming, identifying and localizing danger and take the appropriate action for avoiding the threatening stimuli of the elevated plus-maze. A role for dopaminergic mechanisms in the setting up of adaptive responses in a fear-inducing environment is discussed.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physiology & Behavior - Volume 85, Issue 4, 21 July 2005, Pages 440-447
نویسندگان
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