Effect of 15-KETE on rat isolated pulmonary arterial rings / 中国药理学通报

ABSTRACT

Aim To investigate the effect of 15-ketoeicosatetraenoic acid(15-KETE)and its mechanism through ion channels on rat isolated pulmonary arterial rings by using organ bath technique.Methods Sixteen healthy Wistar rats weighing 220?20 g were divided into two groups(n=8) normoxia group breathing fresh air(FiO_2=21%) and hypoxia group breathing hypoxic air(FiO_2=10%) in a hypoxic box.Pulmonary arteries(PA)were extracted after 9 d and cut into rings(0.5~1.0 mm in diameter and 3 mm in length) for organ bath experiments.Results(1) With increasing concentration from 0 to10~(-6) mol?L~(-1),15-KETE increased PA rings tension gradually in a dosedependent fashion;(2) 4-aminopyridine(2 mmol?L~(-1)),a Kv channel blocker significantly decreased constriction of rat isolated PA rings induced by 15-KETE,and results were similar in two groups;(3) The K_(ATP) channel blocker glyburide(10~(-6)6 mol?L~(-1)) and the BK_(Ca) channel blocker tetraethylammonium(10 mmol?L~(-1)) did not affect constriction of rat isolated PA rings induced by 15-KETE;(4) The BKCa channel blocker nifedipine(10~(-6) mol?L~(-1)) and Ca~(2+)-free Krebs solution significantly decreased constriction of rat isolated PA rings induced by 15-KETE.Conclusion Kv channels play a role in constriction of PA induced by 15-KETE;L-type Ca~(2+) channel blocker and extracellular calcium ion also influence constriction of isolated PA rings induced by 15-KETE.