Behavioral studies suggest that mesencephalic dopamine neurons mediate the rewarding effects of electrical stimulation of the medial forebrain bundle. Yet there is little direct evidence that rewarding electrical stimulation actually activates dopamine-containing neurons. The purpose of the present study was to determine, using in vivo electrochemistry, if electrical stimulation applied to lateral hypothalamic or ventral tegmental reward sites would elicit changes in extracellular levels of dopamine. In vivo high speed chronoamperometric recordings were performed in anesthetized rats that had been previously trained to respond for rewarding electrical stimulation of the medial forebrain bundle or ventral tegmental area. We found that a single 500 msec train of pulses elicited a small transient electrochemical signal, the magnitude of which was dependent on the pulse duration and frequency. This signal was potentiated by inhibition of dopamine reuptake. Prolonged electrical activation with a self-stimulation-like regimen resulted in the gradual accumulation of an electroactive compound, tentatively identified as dihydroxyphenylacetic acid (DOPAC). Taken together, the data reported here support the idea that rewarding electrical stimulation causes the release of dopamine.
|Number of pages||6|
|Journal||Brain Research Bulletin|
|State||Published - Aug 1988|
Bibliographical noteFunding Information:
Supported by NSERC of Canada grant URF0037832 and by USPHS grants NS09199, DA02429, AG06434. Special thanks to Mr. Michael Parrish for expert technical support.
- Brain stimulation reward
- In Vivo electrochemistry
- Medial forebrain bundle
ASJC Scopus subject areas
- Neuroscience (all)