Pheromone-induced expression of immediate early genes in the mouse vomeronasal sensory system.

Immediate early genes (IEGs) are powerful tools for visualizing activated neurons and extended circuits that are stimulated by sensory input. Several kinds of IEGs (e.g., c-fos, egr-1) have been utilized for detecting activated receptor neurons in the pheromone sensory organ called the vomeronasal organ (VNO), as well as for mapping the neurons within the central nervous system (CNS) excited by pheromones.In this chapter, we describe the procedure for the detection of pheromone-induced neural activation in the VNO and CNS using the c-Fos immunostaining technique.