[The role of subtypes of voltage-gated K+ channels in pulmonary vasoconstriction induced by 15-hydroeicosatetraenoic acid].
OBJECTIVE
To observe the effect of subtypes of Kv channels in rat pulmonary artery smooth muscle cells (PASMCs) on the process of pulmonary vasoconstriction induced by 15-HETE.


METHODS
In the present study, ring of rabbit PA with specific Kv channel blockers were employed to functionally identify certain channel subtypes that took part in the process of 15-HETE induced pulmonary vasoconstriction; RT-PCR and Western blotting analysis were also used to measure the expression of subtypes of Kv in PASMCs exposed to 15-HETE,chronic hypoxia.


RESULTS
Blocking of Kv1. 1, Kv1. 2, Kv1. 3 and Kv1. 6 channels did not affect 15-HETE induced vasoconstriction in normoxic rats; 15-HETE did not affect expression of Kv1. 1 and Kv1. 2 channels; 15-HETE significantly downregulated the expression of mRNA and protein of Kv1. 5 and Kv2. 1 in rat PASMCs.


CONCLUSIONS
The results suggested that hypoxia may block Kv1. 5 and Kv2. 1 channels via 15-HETE mediated mechanism, leading to decrease numbers of functional Kv1. 5 and Kv2. 1 channels in PASMCs, leading to PA vasoconstriction.
Li
Qian
Q
College of Pharmacy, Harbin Medical University, Harbin 150086, China.
Zhang
Rong
R
Lü
Chang-Lian
CL
Liu
Yan
Y
Wang
Zhen
Z
Zhu
Da-Ling
DL
D000818:Animals; D015687:Cell Hypoxia; D002478:Cells, Cultured; D006893:Hydroxyeicosatetraenoic Acids / Q000494:pharmacology*; D000860:Hypoxia / Q000503:physiopathology; D051666:Kv1.5 Potassium Channel / Q000096:biosynthesis / Q000235:genetics; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000166:cytology; D032389:Myocytes, Smooth Muscle / Q000166:cytology / Q000378:metabolism*; D024642:Potassium Channels, Voltage-Gated / Q000037:antagonists & inhibitors; D011651:Pulmonary Artery / Q000503:physiopathology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D051669:Shab Potassium Channels / Q000096:biosynthesis / Q000235:genetics; D014661:Vasoconstriction / Q000187:drug effects*
D006893:Hydroxyeicosatetraenoic Acids; D051666:Kv1.5 Potassium Channel; D024642:Potassium Channels, Voltage-Gated; D012333:RNA, Messenger; D051669:Shab Potassium Channels; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid