Adenosine A2A receptor mediated protective effect of 2-(6-cyano-1-hexyn-1-yl)adenosine on retinal ischaemia/reperfusion damage in rats.

Abstract

AIMS:

To determine the effect of 2-(6-cyano-1-hexyn-1-yl)adenosine (2-CN-Ado), an adenosine A2A receptor agonist, on retinal ischaemia/reperfusion damage in rats.

METHODS:

Retinal ischaemia/reperfusion damage was induced by elevating the intraocular pressure of one eye to 130 mm Hg for 60 minutes and returning it to normal. 7 days later, retinal ischaemia/reperfusion damage was histologically quantified by measuring the thickness of retinal layers. Intraocular pressure was measured by pressure transducer.

RESULTS:

Retinal ischaemia/reperfusion caused cell loss in the ganglion cell layer and thinning of the inner plexiform and nuclear layer. Both ocular topical and intravenous administration of 2-CN-Ado caused a reduction of retinal ischaemia/reperfusion damage. A selective A2A receptor antagonist, 1,3,7-trimethyl-8-(3-chlorostyryl) xanthine (CSC), but not a selective A1 receptor antagonist, 8-cyclopentyl-1,3-dipropylxanthine (DPCPX), or a selective A2B receptor antagonist, alloxazine, reduced the protective effect of 2-CN-Ado. While ocular topical administration of 2-CN-Ado caused a sustained reduction of intraocular pressure, intravenous administration of 2-CN-Ado showed a transient ocular hypotensive effect.

CONCLUSIONS:

These results suggest that 2-CN-Ado attenuates retinal ischaemia/reperfusion damage, and at least some of this protective effect of 2-CN-Ado might be mediated via activation of the adenosine A2A receptor.

• Authors: T Konno, A Sato, T Uchibori, A Nagai, K Kogi, N Nakahata
• Journal: The British journal of ophthalmology (Br J Ophthalmol) Vol. 90 Issue 7 Pg. 900-5 (Jul 2006) ISSN: 0007-1161 [Print] England
• PMID: 16613921 (Publication Type: Journal Article)

Chemical References

• 2-(6-cyano-1-hexyn-1-yl)adenosine
• Adenosine A2 Receptor Agonists
• Antihypertensive Agents
• Excitatory Amino Acid Antagonists
• Phenethylamines
• 2-(4-(2-carboxyethyl)phenethylamino)-5'-N-ethylcarboxamidoadenosine
• Dizocilpine Maleate
• Adenosine

Topics

• Adenosine (analogs & derivatives, chemistry, pharmacology, therapeutic use)
• Adenosine A2 Receptor Agonists
• Administration, Topical
• Animals
• Antihypertensive Agents (pharmacology)
• Dizocilpine Maleate (pharmacology)
• Excitatory Amino Acid Antagonists (pharmacology)
• Intraocular Pressure (drug effects)
• Ischemic Preconditioning
• Male
• Phenethylamines (pharmacology)
• Rats
• Rats, Sprague-Dawley
• Reperfusion Injury (metabolism, pathology, prevention & control)
• Retinal Vessels (metabolism, pathology)