Dataset Information

L-DOPA Uptake in Astrocytic Endfeet Enwrapping Blood Vessels in Rat Brain.

ABSTRACT: Astrocyte endfeet surround brain blood vessels and can play a role in the delivery of therapeutic drugs for Parkinson's disease. However, there is no previous evidence of the presence of LAT transporter for L-DOPA in brain astrocytes except in culture. Using systemic L-DOPA administration and a combination of patch clamp, histochemistry and confocal microscopy we found that L-DOPA is accumulated mainly in astrocyte cell bodies, astrocytic endfeet surrounding blood vessels, and pericytes. In brain slices: (1) astrocytes were exposed to ASP(+), a fluorescent monoamine analog of MPP(+); (2) ASP(+) taken up by astrocytes was colocalized with L-DOPA fluorescence in (3) glial somata and in the endfeet attached to blood vessels; (4) these astrocytes have an electrogenic transporter current elicited by ASP(+), but intriguingly not by L-DOPA, suggesting a different pathway for monoamines and L-DOPA via astrocytic membrane. (5) The pattern of monoamine oxidase (MAO type B) allocation in pericytes and astrocytic endfeet was similar to that of L-DOPA accumulation. We conclude that astrocytes control L-DOPA uptake and metabolism and, therefore, may play a key role in regulating brain dopamine level during dopamine-associated diseases. These data also suggest that different transporter mechanisms may exist for monoamines and L-DOPA.

SUBMITTER: Inyushin MY

PROVIDER: S-EPMC3409556 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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L-DOPA Uptake in Astrocytic Endfeet Enwrapping Blood Vessels in Rat Brain.

Inyushin M Y MY Huertas A A Kucheryavykh Y V YV Kucheryavykh L Y LY Tsydzik V V Sanabria P P Eaton M J MJ Skatchkov S N SN Rojas L V LV Wessinger W D WD

Parkinson's disease 20120724

Astrocyte endfeet surround brain blood vessels and can play a role in the delivery of therapeutic drugs for Parkinson's disease. However, there is no previous evidence of the presence of LAT transporter for L-DOPA in brain astrocytes except in culture. Using systemic L-DOPA administration and a combination of patch clamp, histochemistry and confocal microscopy we found that L-DOPA is accumulated mainly in astrocyte cell bodies, astrocytic endfeet surrounding blood vessels, and pericytes. In brai ...[more]

PMID: 22888467

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Dataset Information

L-DOPA Uptake in Astrocytic Endfeet Enwrapping Blood Vessels in Rat Brain.

Publications

L-DOPA Uptake in Astrocytic Endfeet Enwrapping Blood Vessels in Rat Brain.

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