Coupling Factor 6 Is Upregulated in Monocrotaline-Induced Pulmonary Arterial Hypertension Rats

Abstract Background Pulmonary arterial hypertension (PAH) is a rare and fatal disease. The prostacyclin (PGI2 ) pathway is a well-known therapeutic target for PAH. As a novel vasoconstrictive peptide, coupling factor 6 (CF6) has been recognized as the only endogenous inhibitor of PGI2 . However, the relationship between CF6 and PAH is still unknown. Objective In this study, we investigated the involvement of CF6 in PAH in rats. Methods and results A total of 80 Sprague-Dawley rats were randomly divided into two groups: a control group (with saline intraperitoneally) and a monocrotaline (MCT)-treated group (with MCT 60mg/kg ip). The expression level of CF6 was measured by Immunohistochemistry, RT-PCR, and ELISA. The plasma level of 6-keto-PGF1α , a stable metabolite of PGI2 , was measured by ELISA. After MCT injection, while the plasma level of CF6 was markedly increased in a time-dependent manner, the level of 6-keto-PGF1α was decreased in the MCT rats as compared to that in the controls ( P