ATP-Induced Relaxation of Porcine Retinal Arterioles Depends on the Perivascular Retinal Tissue and Acts Via an Adenosine Receptor

Abstract

Purpose: Purinergic compounds and cyclooxygenase inhibitors are involved in the tone regulation of isolated retinal arterioles in vitro, but it is unknown whether the perivascular retinal tissue influences these effects. Methods: Adenosine-and ATP-induced vasodilation of porcine retinal arterioles was studied in a wire myograph before and after removal of the perivascular tissue. Results: Both adenosine and ATP caused relaxation of the studied arterioles. This effect depended on the perivascular tissue and could be blocked by antagonists but was unaffected by ibuprofen. Conclusions: The relaxation of porcine retinal arterioles induced by purinergic compounds is modulated by the perivascular retinal tissue.

KEYWORDS:

• adenosine
• ATP
• metabolic autoregulation
• perivascular tissue
• retinal vascular tone