%0 Journal Article %T The <i>in Vitro</i> Characterisation of the Effect of Selexipag on Small Human Pulmonary Arteries %A Salman Arif %A Mohamed Abdi %A Bilal Qaddoura %A Ghazi Elshafi %A Syed Qadri %A Mubarak Chaudhry %A Mahmoud Loubani %A Azar Hussain %J World Journal of Cardiovascular Surgery %P 293-303 %@ 2164-3210 %D 2022 %I Scientific Research Publishing %R 10.4236/wjcs.2022.1212026 %X Objective: There is a lack of data on the direct effects of Selexipag, a novel prostacyclin Inositol phosphate-3 receptor (IP3) agonist with a long half-life, on human pulmonary arteries. This study aims to establish the efficacy and potency of Selexipag on human pulmonary arteries. Methods: Patient consent was obtained prior to lung resection for primary lung cancer. The pulmonary artery rings (n = 23 from 6 patients) were cut to 2 - 4 mm length and 2 - 4 mm internal diameter. They were mounted on a wire myograph under physiological conditions and were pre-constricted to prostaglandin F2¦Á. Concentration response curves were constructed to Selexipag by cumulative addition to the myograph chambers. The viability of the rings was confirmed with Acetylcholine and potassium chloride. Results: The Selexipag caused dose dependent vasodilation to human pulmonary arteries. The range of doses used was from 1 pM to 30 uM, n = 4 were excluded due to non-reactivity and n = 19 were included. Initial significant vasodilation of PAs was noted at 3 uM. Maximal response was achieved at 10