An Island of Reil excitation: Mapping glutamatergic (vGlut1+ and vGlut2+) connections in the medial insular cortex.

The insular cortex is a multifunctional and richly connected region of the cerebral cortex, critical in the neural integration of external stimuli and internal signals. Well-served for this role by a large network of afferent and efferent connections, the mouse insula can be simplified into an anterior, medial and posterior portion. Here we focus on the medial subregion, a once over-looked area that has gained recent attention for its involvement in an array of behaviours.

Distribution of the orexin-1 receptor (OX1R) in the mouse forebrain and rostral brainstem: A characterisation of OX1R-eGFP mice.

We have utilised a transgenic reporter mouse in which green fluorescent protein (GFP) expression is driven by the orexin-1 receptor (OX1R) promoter to systematically map the distribution of OX1R-expressing neurons throughout the mouse forebrain and rostral brainstem. GFP labelling was observed in perikarya and fibres in an extensive range of brain loci encompassing the olfactory and cerebral cortices, dorsal and ventral pallidum, hippocampus, amygdaloid regions, septal areas, thalamic nuclei, hypothalamic nuclei and several brainstem regions, consistent with previous studies of OX1R mRNA expression. This is the first study to systematically characterise the neuroanatomical distribution of OX1R in the OX1R-eGFP mouse, confirming its veracity as a faithful reporter of OX1R expression and utility for future studies assessing the role of OX1R in more complex behaviours.