Auditory-conditioned-fear-dependent c-Fos expression is altered in the emotion-related brain structures of Fyn-deficient mice

Impaired extinction of learned fear in rats selectively bred for high anxiety – evidence of altered neuronal processing in prefrontal‐amygdala pathways

“…It will be necessary in future studies to perform c‐Fos double‐labelling experiments with markers for GABAergic and glutamatergic neurons, for example, to differentiate between (pheno)types of activated cells in the amygdala and mPFC (see below). Interestingly, Kubota et al. (2004) also revealed that the number of c‐Fos‐positive cells was increased in the central amygdala and reduced in the BLA and LA after an extinction trial in anxious Fyn(−/−) mice compared with low anxious Fyn(+/−) mice.…”

Altered brain activity processing in high-anxiety rodents revealed by challenge paradigms and functional mapping

“…This was necessary since only under these conditions a difference in time spent in the open arm between the genotypes was detectable. Using an auditory fear-conditioning paradigm, Kubota et al (2004) observed that the enhanced freezing response during 5 min tone (CS) presentation in Fyn-tyrosine kinase knockout mice as compared with heterocygotes is associated with enhanced Fos response in parts of the amygdala (including medial, basomedial, central and cortical nuclei), the PVN, lateral hypothalamus and parts of the PAG, while attenuated Fos response was noted in basolateral and lateral nuclei of the amygdala. The authors concluded that the enhanced excitability of the origins and targets of the amygdalo-hypothalamic and amygdalo-midbrain projection systems elicits enhanced emotional reactions and is related to the increased fearfulness of Fyn-tyrosine knockout mice.…”

Molecular Mechanisms of Threat Learning in the Lateral Nucleus of the Amygdala

“…170 Moreover, blockade of Src was shown to reduce surface expression of GluN2B-containing receptors and synaptic plasticity in amygdala neurons. 171 On the other hand, animals lacking Fyn, a SFK, show increased threat reactions, 172 and Fynoverexpressing animals show the opposite behavior. 166 Kinase activity initiated as a consequence of NMDAR activity can lead to phosphorylation of NMDAR residues that regulate its coupling to signaling complexes and the activity of such complexes.…”