Adenosine transport inhibition ameliorates postischemic hypoperfusion in pigs

Area of Science:

• Neuroscience
• Cerebrovascular Medicine
• Pharmacology

Background:

• Cerebral ischemia can lead to delayed hypoperfusion, exacerbating tissue injury.
• Adenosine plays a crucial role in regulating cerebral blood flow.
• Understanding adenosine's role in post-ischemic hypoperfusion is vital for developing neuroprotective strategies.

Purpose of the Study:

• To investigate whether augmenting interstitial adenosine can improve tissue perfusion following cerebral ischemia.
• To test the hypothesis that inhibiting adenosine transport enhances post-ischemic blood flow.

Main Methods:

• Global cerebral ischemia was induced in newborn pigs.
• Local cortical blood flow and interstitial purine metabolites were measured using hydrogen clearance-microdialysis.
• One group received nitrobenzyl-thioinosine (NBTI) to inhibit adenosine transport.

Main Results:

• NBTI treatment increased baseline interstitial adenosine levels and cortical blood flow.
• Inhibition of adenosine transport significantly lessened post-ischemic hypoperfusion.
• NBTI-treated animals showed reduced reductions in cortical blood flow during reperfusion compared to controls.

Conclusions:

• Inhibiting adenosine transport elevates interstitial adenosine concentration during and after cerebral ischemia.
• This elevation improves cortical perfusion in the post-ischemic period.
• Adenosinergic therapy may offer neuroprotection in cerebral ischemia by enhancing perfusion.