The neostriatal mosaic: compartmentalization of corticostriatal input and striatonigral output systems
Abstract
The striatum (caudate-putamen) of the basal ganglia in the mammalian forebrain is a mosaic of two interdigitating, neurochemically distinct compartments. One type, the `patch' compartment, is identified by patches of dense opiate receptor binding1,2, and is enriched in enkephalin- and substance P-like immunoreactivity3. The other compartment, the `matrix', has a high acetyl-cholinesterase activity2,4, and is shown here to have a dense plexus of fibres displaying somatostatin-like immunoreactivity. The present study demonstrates the two compartments have distinct connections, using a method that concurrently reveals striatal input, output and neurochemical systems in the rat. Patches receive inputs from the prelimbic cortex (a medial frontal cortical area with direct `limbic' inputs from the amygdala5 and hippocampus6,7); they also project to the substantia nigra pars compacta (the source of the nigrostriatal dopaminergic system). Conversely, the matrix receives inputs from sensory and motor cortical areas8; here it is shown to project to the substantia nigra pars reticulata (the source of the non-dopaminergic nigrothalamic and nigrotectal system9,10). Also, an intrinsic striatal somatostatin-immunoreactive system is described that may provide a link between the two compartments. The striatal patch and matrix compartments thus appear to be functionally distinct and interactive parallel input-output processing channels.
- Publication:
-
Nature
- Pub Date:
- October 1984
- DOI:
- 10.1038/311461a0
- Bibcode:
- 1984Natur.311..461G