@article{APS3869,
author = {Kwok Fu Jacobus NG and Susan Wai Sum Leung and Ricky Ying Keung Man and Paul M Vanhoutte},
title = {Endothelium-derived hyperpolarizing factor mediated relaxations in pig coronary arteries do not involve Gi/o proteins},
journal = {Acta Pharmacologica Sinica},
volume = {29},
number = {12},
year = {2016},
keywords = {},
abstract = {Aim: Endothelium-dependent relaxations to certain neurohumoral substances are mediated by pertussis toxin-sensitive Gi/o protein. Our experiments were designed to determine the role, if any, of pertussis toxin-sensitive G-proteins in relaxations attributed to endothelium-derived hyperpolarizing factor (EDHF).
Methods: Pig coronary arterial rings with endothelia were suspended in organ chambers filled with Krebs-Ringer bicarbonate solution maintained at 37 °C and continuously aerated with 95%O2 and 5% CO2. Isometric tension was measured during contractions to prostaglandin F2α in the presence of indomethacin and Nω-nitro-L-arginine methyl ester (L-NAME).
Results: Thrombin, the thrombin receptor-activating peptide SFLLRN, bradykinin, substance P, and calcimycin produced dose-dependent relaxations. These relaxations were not inhibited by prior incubation with pertussis toxin, but were abolished upon the addition of charybdotoxin plus apamin. Relaxations to the α2-adrenergic agonist UK14304 and those to serotonin were abolished in the presence of indomethacin and L-NAME.
Conclusion: Unlike nitric oxide-mediated relaxations, EDHF-mediated relaxations of pig coronary arteries do not involve pertussis toxin-sensitive pathways and are Gi/o protein independent.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/3869}
}