Electrophysiological Study of the Neostriatum in Brain Slice Preparation

Abstract

The neostriatum of mammalian species consists of the caudate and the putaman and is a major component of the basal ganglia (Carpenter, 1981). It is a relatively large nuclear mass and is easily dissected from the rest of the brain. In slice preparation, the neostriatum is severed from extrinsic connections. Neuronal responses recorded following electrical stimulation of the neostriatum in slice preparation therefore reflect only the activities of those neuronal elements left intact. These would include the soma, dendrites, and, so long as their course remains within the slice, axons of neostriatal neurons. Added to these are fibers of extrinsic origin and their terminals, isolated from their cell bodies, but remaining electrically excitable. The slice preparation therefore would be well suited to the study of local interactions among striatal neuronal elements and the action of monosynaptic afferents. The slice preparation enables the investigator to manipulate the extracellular milieu in a controlled manner. For this reason, it is also well suited for studying the action of putative neurotransmitters and other agents on the electrical activities of neurons and characterizing the relationships between these membrane activities and specific electrolytes.