Neurochemical fingerprinting of amygdalostriatal and intra-amygdaloid projections: a tracing–immunofluorescence study in the rat

Publication date: Available online 6 November 2018Source: Journal of Chemical NeuroanatomyAuthor(s): Floris G. Wouterlood, Sanne van Oort, Lucian Bloemhard, Nico A. Flierman, Jorik Spijkerman, Chris I. Wright, Jeroen A.M. Beliën, Hendrik J. GroenewegenAbstractAmygdalostriatal and intra-amygdaloid fiber connectivity was studied in rats via injections of one of the tracers Phaseolus vulgaris leucoagglutinin (PHA-L) or biotinylated dextran amine (BDA) into various amygdaloid nuclei. To determine the neurotransmitter identity of labeled fibers we combined tracer detection with immunofluorescence staining, using antibodies against vesicular transporters (VTs) associated with glutamatergic (VGluT1, VGluT2) or GABAergic (VGAT) neurotransmission. High-magnification confocal laser scanning images were screened for overlap: occurrence inside tracer labeled fibers or axon terminals of immunofluorescence signal associated with one of the VTs.Labeled amygdalostriatal fibers were seen when tracer had been injected into the magnocellular and parvicellular portions of the basal amygdaloid nucleus and the lateral amygdaloid nucleus (nuclei belonging to 'cortical type' amygdaloid nuclei). Intra-amygdaloidal projection fibers were mostly found after tracer injections in the central and medial amygdaloid nuclei ('striatal type' amygdaloid nuclei).Terminals of tracer-labeled amygdalostriatal fibers contained immunofluorescence signal associated mostly with VGluT1 and to a lesser degree with VGlu...
Source: Journal of Chemical Neuroanatomy - Category: Neuroscience Source Type: research