Hoseini M, Hajizadeh S, Fathollahi Y, Golmohammadi M, Erfani B, Heidarian Pour A. The role of adenosine A2 receptors in regulation of pial vessels blood flow in anesthetized morphine dependent rats.. Physiol Pharmacol 2008; 12 (1) :22-30
URL:
http://ppj.phypha.ir/article-1-369-en.html
Abstract: (11978 Views)
Introduction:Adenosine as a potent vasodilator has physiological role in regulation of regional cerebral blood flow (rCBF).
Metod: Laser-Dِoppler flowmetry technique was used to study pial vessels blood flow responses to adenosine receptors agonists and antagonist. Male Sprague Dawley rats (250-350g) that were housed in standard conditions, were anesthetized with Urethane (1.5g/kg). Adenosine (general agonist), NECA (A2Aand A2B receptor agonist) and CGS-21380(A2Aselective agonist), were used in absence and presence of A2A receptors- selective antagonist, ZM-243185, in naive and morphine-dependent rats.
Results: Adenosine, NECA and CGS-21680 increased pial vessels blood flow in naive and dependent rats dose dependently. These responses were blocked significantly by ZM-243185. Responses of pial vessels to adenosine (10-4, 10-5, 10-6 M) and NECA (10-4, 10-5, 10-6 M) were increased significantly in morphine- dependent rats in comparison to naive rats. Pial vessels responses to CGS-21680 had not shown any significant deferences between morphine- dependent and naive rats.
Conclusion:Based on these results it could be concluded that the role of A2B receptors in regulation of rCBF in morphine-dependent rats is more effective than A2A receptors.