Publications by authors named "Samira Omoumi"
Purpose: The infralimbic (IL) subregion of the medial prefrontal cortex (mPFC) regulates the extinction of conditioned fear memory. Glucocorticoid and gamma-aminobutyric acid (GABA) receptors are expressed in the mPFC and are also critical in fear extinction. This study investigated the possible interactive effects of the glucocorticoids and GABAergic system in the IL on the regulation of fear extinction.
View Article and Find Full Text PDFGlucocorticoid administration, before or after fear memory reactivation, impairs subsequent fear memory expression, but the underlying mechanisms are not well understood. The present study examined the role of basolateral amygdala (BLA) β-adrenoceptors in the effects of intra-BLA corticosterone injection on fear memory in rats. Bilateral cannulae were implanted in the BLA of Wistar male rats.
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- This study explored how glucocorticoids and GABA receptors in the infralimbic cortex affect fear extinction in rats during an auditory fear conditioning task.
- Rats were conditioned with tones and footshocks, followed by extinction trials after receiving corticosterone, which enhanced their ability to extinguish fear.
- Co-administration of GABA antagonists blocked the effects of corticosterone, showing that glucocorticoid receptors and GABA receptors work together through the ERK pathway to modulate fear extinction.
Introduction: The basolateral amygdala (BLA) and infralimbic area (IL) of the medial prefrontal cortex (mPFC) are two interconnected brain structures that mediate both fear memory expression and extinction. Besides the well-known role of the BLA in the acquisition and expression of fear memory, projections from IL to BLA inhibit fear expression and have a critical role in fear extinction. However, the details of IL-BLA interaction have remained unclear.
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- Disruptions in the light/dark cycle negatively impact memory formation and retrieval in both humans and animals, particularly observed through animal studies.
- A study involving adult male Wistar rats divided them into two groups: one with a normal light/dark cycle and another kept in constant darkness for three weeks, with performance measured using the Morris Water maze and auditory fear conditioning tests.
- Rats in constant darkness showed impaired spatial memory retrieval and enhanced extinction of auditory fear memory during the light phase and had altered BDNF/TRKB protein levels in the hippocampus, indicating serious effects on their neural function compared to those in regular light/dark conditions.