Effect of iptakalim on HIF-1α in lung tissues of rats with chronic hypoxic pulmonary hypertension

Objective To investigate the effects of iptakalim,a novel ATP sensitive potassium channel opener(KATPCO),on HIF-1α in lung tissues of rats with chronic hypoxic pulmonary hypertension(HPH).Methods Thirty-six male SD rats were randomly divided into three groups with 12 rats each.Rats in group C and group HPH were given normal saline 5ml·kg-1·d-1.Rats in group IPT were given IPT 1.5ml·kg-1·d-1 ig.The rats in groups of HPH and IPT were exposed to normobaric(10.0±0.5)% oxygen environment for 8 hours a day,6 days a week,for 4 weeks.Reverse transcription polymerase chain reaction(RT-PCR) and Western blot were used to detect the expression of hypoxia-inducible factor-1α(HIF-1α) mRNA.Results Mean pulmonary arterial pressure(MPAP),the weight ratio of right ventricle(RV) to left ventricle plus septum(LV+S),and the expression of HIF-1α mRNA were significantly higher in group HPH than those in group C(P0.01).There was no significant difference in the expression of HIF-1α mRNA between group HPH and group IPT.Conclusion Iptakalim can effectively relieve HPH,which may be related to the inhibition of the expression of HIF-1α in the lung tissues.