Genetic and Functional Cartography of the Central Amygdala

Abstract

The central nervous system includes an array of neuronal types classified across multiple features. Genetic dissection of the lateral division of the central amygdala (CeAl) has revealed two functionally distinct neuronal populations expressing the relatively non-overlapping molecular markers, protein kinase C δ (PKCδ) and somatostatin (SOM). Here, I leverage genetic access to neurons expressing the receptor for calcitonin gene-related peptide (CGRPR) to uncover the entire CeAl. Despite rostrocaudal gradients of PKCδ+ and SOM+ neurons, CGRPR+ neurons are present across its entire axis. In the caudal CeAl, CGRPR+ neurons coexpress PKCδ and SOM, although to differing extents. Like CGRPR expression, functional activation by satiety recruits the entire CeAl. Hence, these data urge an update to CeAl cell types and their activation. Future monitoring and manipulation of the CeAl must be aware of potential genetic gradients.