Substantia nigra reticulata striatal input

Fig. 24. Patch and matrix striatal compartments are labeled with neurochemical markers. A) The patch compartment is labeled with 3H-naloxone binding to mu opiate receptors (white in the darkfield photomicrograph). B) The matrix compartment is labeled with calbindin-immunoreactivity, which labels spiny projection neurons that provide inputs to the substantia nigra pars reticulata. The correspondence between calbindin-poor zones (black arrows) and mu opiate binding sites (white arrows) is seen to occur in all regions of the striatum. Calbindin-immunoreactivity is relatively weak in the dorso-lateral striatum, which nonetheless contains opiate receptor patches.

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