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Interactions between adenosine and nifedipine in the rat cerebral cortex
J W Phillis1, T H Swanson, R A Barraco
1Department of Physiology, School of Medicine, Wayne State University, Detroit, MI 48201 USA.
Neurochemistry International
|May 22, 2010
Summary
Nifedipine, a calcium channel blocker, was found to inhibit adenosine uptake in rat brain cells. This suggests that some of nifedipine's effects might be linked to its interaction with adenosine signaling pathways.
Area of Science:
- Neuropharmacology
- Calcium channel blockers
- Adenosine signaling
Background:
- Nifedipine is a known calcium-channel antagonist.
- Adenosine plays a role in neurotransmission and neuronal function.
- The interaction between calcium channels and adenosine signaling is not fully understood.
Purpose of the Study:
- To investigate the effect of nifedipine on adenosine uptake in the rat brain.
- To explore the potential role of adenosine in mediating nifedipine's calcium-antagonist actions.
Main Methods:
- Inhibition of [(3)H]adenosine uptake into rat cerebral cortical synaptosomes.
- Iontophoretic application of nifedipine onto rat cerebral cortical neurons.
- Measurement of spontaneous neuronal firing rates.
Main Results:
- Nifedipine inhibited [(3)H]adenosine uptake with an IC(50) of 1.1 ?M.
- Nifedipine potentiated the depressant effects of adenosine on spontaneous neuronal firing.
Conclusions:
- Nifedipine interferes with adenosine uptake in the brain.
- Adenosine may contribute to some of the calcium-antagonist effects of nifedipine.
- This study highlights a potential interplay between nifedipine and adenosine signaling in the central nervous system.
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