Expression and conditioned inhibition of fear-potentiated startle after stimulation and blockade of AMPA/Kainate and GABA(A) receptors in the dorsal periaqueductal gray.
نویسنده
چکیده
Previous work showed that the dorsal periaqueductal gray is involved in the inhibition of fear-potentiated startle. The present study investigated the effects of blockade and stimulation of Kainate/AMPA and GABA(A) receptors within the dorsal periaqueductal gray on expression and conditioned inhibition of fear-potentiated startle. Blockade of the Kainate/AMPA receptors enhanced whereas stimulation of the Kainate/AMPA receptors decreased expression of fear-potentiated startle. These effects do not reflect conditioned inhibition since this modulation was not changed by injections of Kainate/AMPA receptor agonists or antagonists into the dorsal periaqueductal gray. Stimulation and blockade of GABA(A) receptors within the dorsal periaqueductal gray neither affected expression of fear-potentiated startle nor its conditioned inhibition. The present results together with findings from the literature indicate that glutamate in the dorsal periaqueductal gray is a critical substrate for the expression and modulation of fear-related behaviours.
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ورودعنوان ژورنال:
- Brain research
دوره 880 1-2 شماره
صفحات -
تاریخ انتشار 2000