Related Experiment Videos
Adenosine A2a receptor mRNA is expressed by enkephalin cells but not by somatostatin cells in rat striatum: a
1Department of Neurobiology, AFRC Babraham Institute, Cambridge UK.
Abstract:
The cellular co-expression of adenosine A2a receptor mRNA and preproenkephalin A (PPE A) mRNA and A2a receptor mRNA and prosomatostatin (pSRIF) mRNA in rat striatum was studied using a combination of radioactive and non-radioactive in situ hybridization techniques. Cells containing adenosine A2a receptor mRNA were visualised using an 35S-labelled oligonucleotide whilst those containing PPE A mRNA and pSRIF mRNA were detected using alkaline phosphatase-labelled antisense oligonucleotides; both radioactive and non-radioactive hybridization signals were visualized on the same tissue section. Bright field examination of striatal sections hybridized with both the [35S]adenosine A2a receptor probe and the alkaline phosphatase-labelled PPE A probe revealed dense clusters of silver grains overlying cells containing alkaline phosphatase reaction product demonstrating that the two gene transcripts were expressed by the same medium-sized nerve cells. The cellular expression of the two mRNAs was consistently found to be concordant demonstrating that adenosine A2a receptor mRNA is expressed by medium-sized striatal enkephalin cells. In contrast, clusters of silver grains were never detected overlying striatal cells containing pSRIF mRNA indicating that this population of interneurones do not express the adenosine A2a receptor sub-type. The expression of adenosine A2a receptors by enkephalin cells in striatum suggests that adenosine may play a role in modulating the activity of GABA/enkephalin striatopallidal neurones through interaction with A2a receptors.
Insights
Adenosine A2a receptors are expressed in medium-sized striatal enkephalin cells, but not in prosomatostatin interneurons. This suggests adenosine modulates GABA/enkephalin striatopallidal neuron activity.
Area of Science:
- Neuroscience
- Molecular Biology
- Receptor Pharmacology
Background:
- Adenosine receptors play crucial roles in the central nervous system.
- The striatum is a key brain region involved in motor control and reward.
- Understanding receptor co-expression provides insights into neuronal circuitry and function.
Purpose of the Study:
- To investigate the cellular co-expression of adenosine A2a receptor mRNA with preproenkephalin A (PPE A) mRNA and prosomatostatin (pSRIF) mRNA in the rat striatum.
- To determine if adenosine A2a receptors are expressed in specific neuronal populations within the striatum.
Main Methods:
- Utilized a combination of radioactive and non-radioactive in situ hybridization techniques.
- Visualized adenosine A2a receptor mRNA using 35S-labelled oligonucleotides.
- Detected PPE A mRNA and pSRIF mRNA using alkaline phosphatase-labelled antisense oligonucleotides on the same tissue sections.
Main Results:
- Demonstrated co-localization of adenosine A2a receptor mRNA and PPE A mRNA in the same medium-sized striatal nerve cells.
- Confirmed that adenosine A2a receptor mRNA is expressed by medium-sized striatal enkephalin cells.
- Found no co-expression of adenosine A2a receptor mRNA with pSRIF mRNA in striatal interneurons.
Conclusions:
- Adenosine A2a receptors are specifically expressed by striatal enkephalin-containing neurons.
- Striatal interneurons expressing prosomatostatin do not co-express adenosine A2a receptors.
- Adenosine may modulate the activity of GABA/enkephalin striatopallidal neurons via A2a receptor interaction.