Dataset Information

D2-like receptor activation does not initiate a brain docosahexaenoic acid signal in unanesthetized rats.

ABSTRACT:

Background

The polyunsaturated fatty acid, docosahexaenoic acid (DHA), participates in neurotransmission involving activation of calcium-independent phospholipase A2 (iPLA2), which is coupled to muscarinic, cholinergic and serotonergic neuroreceptors. Drug induced activation of iPLA2 can be measured in vivo with quantitative autoradiography using 14C-DHA as a probe. The present study used this approach to address whether a DHA signal is produced following dompaminergic (D)2-like receptor activation with quinpirole in rat brain. Unanesthetized rats were infused intravenously with 14C-DHA one minute after saline or quinpirole infusion, and serial blood samples were collected over a 20-minute period to obtain plasma. The animals were euthanized with sodium pentobarbital and their brains excised, coronally dissected and subjected to quantitative autoradiography to derive the regional incorporation coefficient, k*, a marker of DHA signaling. Plasma labeled and unlabeled unesterified DHA concentrations were measured.

Results

The incorporation coefficient (k*) for DHA did not differ significantly between quinpirole-treated and control rats in any of 81 identified brain regions. Plasma labeled DHA concentration over the 20-minute collection period (input function) and unlabeled unesterified DHA concentration did not differ significantly between the two groups.

Conclusion

These findings demonstrate that D2-like receptor initiated signaling does not involve DHA as a second messenger, and likely does not involve iPLA2 activation.

SUBMITTER: Taha AY

PROVIDER: S-EPMC4295280 | biostudies-literature | 2014 Oct

REPOSITORIES: biostudies-literature

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Publications

D2-like receptor activation does not initiate a brain docosahexaenoic acid signal in unanesthetized rats.

Taha Ameer Y AY Chang Lisa L Chen Mei M Rapoport Stanley I SI Ramadan Epolia E

BMC neuroscience 20141030

<h4>Background</h4>The polyunsaturated fatty acid, docosahexaenoic acid (DHA), participates in neurotransmission involving activation of calcium-independent phospholipase A2 (iPLA2), which is coupled to muscarinic, cholinergic and serotonergic neuroreceptors. Drug induced activation of iPLA2 can be measured in vivo with quantitative autoradiography using 14C-DHA as a probe. The present study used this approach to address whether a DHA signal is produced following dompaminergic (D)2-like receptor ...[more]

PMID: 25359512

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Dataset Information

D2-like receptor activation does not initiate a brain docosahexaenoic acid signal in unanesthetized rats.

Background

Results

Conclusion

Publications

D2-like receptor activation does not initiate a brain docosahexaenoic acid signal in unanesthetized rats.

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