Contextual Processing elicits Sex Differences in Dorsal Hippocampus Activation following Footshock and Context Fear Retrieval.

Contextual Processing elicits Sex Differences in Dorsal Hippocampus Activation following Footshock and Context Fear Retrieval. Behav Brain Res. 2020 Jun 16;:112771 Authors: Colon LM, Poulos AM Abstract Establishing a contextual representation of an environment places specific spatial-temporal processing demands on the mammalian hippocampus, a region showing sex-differences in processing capabilities. However, evidence for sex differences in these processing demands during contextual fear learning remains limited. Here, we examined the relationship among contextual processing, timing of footshock, and activation of the dorsal hippocampus and basolateral amygdalar nuclei (BLA) in male and female mice (C57Bl/6 J). We modified the initial exposure time to the conditioning context prior to administration, or not, of a single footshock. We then quantified Fos- ir neurons activated by acquisition or retrieval of contextual fear memories in the rostral half of the dorsal CA1 (proximal - distal regions), CA3, Dentate Gyrus and basolateral amygdalar nuclei corresponding to atlas levels of the Allen Reference Atlas. In experiment 1, we found that sex differences in context elicited freezing were evident at the longest context placement-to-shock interval and that context fear retrieval with increasing contextual exposure periods increased CA1 Fos-ir in males, but not females. In experiment 2, we observed that an aversive footshock in males pot...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research