Effect of dichloroacetate on expression of Kv1.5 in a rat model of pulmonary arterial hypertension / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of dichloroacetate on the expression of Kv1.5 in a rat model of pulmonary arterial hypertension (PAH) .Methods Thirty-two male SD rats weighing 200-250 g were randomly divided into 4 groups ( n = 8 each): normal control group (group C), dichloroacetate control group (group D),PAH group, and PAH + dichloroacetate group (group PD). PAH was induced by left lung resection combined with subcutaneous injection of monocrotaline 60 mg/kg in PAH and PD groups. In group PD, dichloroacetate 80 mg/kg was given through a gastric tube into stomach once a day for 28 consecutive days after monocrotaline injection,while the equal volume of normal saline was given instead of dichloroacetate in group PAH. Group D only received dichloroacetate 80 mg/kg through a gastric tube into stomach once a day for 28 consecutive days. Pulmonary arterial pressure (PAP) was measured at day 28 after monocrotaline injection. The rats were then sacrificed and lung tissues were removed to calculate the percentage of thickness of the tunica media of pulmonary artery and right venicular hypertrophy index and to determine the proliferating cell nuclear antigen (PCNA) and Kv1.5 protein expression (by Western blot) and Kv1.5 mRNA expression (by RT-PCR).Results Compared with group C, the PAP,percentage of thickness of the tunica media, right ventricular hypertrophy index were significantly increased, Kv1.5 mRNA and protein expression was down-regulated and PCNA expression was up-regulated in groups PAH and PD ( P ＜ 0.05). Compared with group PAH, the PAP, percentage of thickness of the tunica media, right ventricular hypertrophy index were significantly decreased, Kv1.5 mRNA and protein expression was up-regulated and PCNA expression was down-regulated in group PD (P ＜ 0.05). There was no significant difference in the indexes mentioned above between group C and group D ( P ＞ 0.05). Conclusion Dichloroacetat alleviates PAH through upregulating Kv1.5 expression in lung tissues and inhibiting pulmonary vascular remodeling in rats.