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Updated: Jun 21, 2026

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Preparation and In Vivo Use of an Activity-based Probe for N-acylethanolamine Acid Amidase
Published on: November 23, 2016
Dopamine-sensitive adenylate cyclase: location in substantia nigra
Summary
Dopamine receptors in the rat substantia nigra are not on dopamine cells. Instead, they are on pathways projecting from the forebrain, involving GABA or substance P.
Area of Science:
- Neuroscience
- Neurochemistry
Background:
- Dopamine-sensitive adenylate cyclase exists in the rat substantia nigra.
- Its characteristics resemble those found in the striatum.
Purpose of the Study:
- To determine the location of dopamine receptors in the substantia nigra.
- To investigate whether these receptors are on dopamine cell bodies or associated pathways.
Main Methods:
- Lesioning studies in rats.
- Intranigral 6-hydroxydopamine application to destroy dopamine cell bodies.
- Brain hemitransection and circumscribed lesions of striatonigral pathways.
Main Results:
- Destroying dopamine cell bodies did not abolish dopamine's effect on nigral adenylate cyclase.
- Lesioning striatonigral pathways abolished dopamine stimulation of adenylate cyclase in the substantia nigra.
Conclusions:
- Dopamine receptors in the substantia nigra are not located on dopamine cell bodies.
- These receptors are associated with afferent pathways, potentially involving GABA or substance P, projecting from the forebrain.
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