Quantified Coexpression Analysis of Central Amygdala Subpopulations

Abstract

Molecular identification and characterization of fear controlling circuitries is a promising path towards developing targeted treatments of fear-related disorders. Three-color <i>in situ</i> hybridization analysis was used to determine whether somatostatin (SOM, <i>Sst</i>), neurotensin (NTS, <i>Nts</i>), corticotropin-releasing factor (CRF, <i>Crf</i>), tachykinin 2 (TAC2, <i>Tac2</i>), protein kinase c-δ (PKC-δ, <i>Prkcd</i>), and dopamine receptor 2 (DRD2, <i>Drd2</i>) mRNA colocalize in male mouse amygdala neurons. Expression and colocalization was examined across capsular (CeC), lateral (CeL), and medial (CeM) compartments of the central amygdala. The greatest expression of <i>Prkcd</i> and <i>Drd2</i> were found in CeC and CeL. <i>Crf</i> was expressed primarily in CeL, while <i>Sst</i>-, <i>Nts</i>-, and <i>Tac2</i>-expressing neurons were distributed between CeL and CeM. High levels of colocalization were identified between <i>Sst</i>, <i>Nts</i>, <i>Crf</i>, and <i>Tac2</i> within the CeL, while little colocalization was detected between any mRNAs within the CeM. These findings provide a more detailed understanding of the molecular mechanisms that regulate the development and maintenance of fear and anxiety behaviors.