Downregulation of Kir6.1/SUR2B channels in the obese rat aorta.
OBJECTIVE
This study was designed to evaluate the contribution of adenosine triphosphate-dependent potassium channels to the increase in blood pressure observed in obese rats.


METHODS
The experiment was performed in male Sprague-Dawley rats. Glibenclamide-sensitive currents were measured in vascular smooth muscle cells by patch-clamp. Expressions of Kir6.1 and SUR2B were examined by reverse transcription polymerase chain reaction and western blot techniques, respectively.


RESULTS
In the aortic vascular smooth muscle cells, pinacidil induced glibenclamide-sensitive currents. The current from obese rats was significantly lower (-10.55 +/- 1.63 pA/pF) compared with that from the control rats (-20.18 +/- 2.79 pA/pF). Expressions of Kir6.1 and SUR2B were downregulated in vascular smooth muscle cells of aortas from the obese rats.


CONCLUSIONS
These findings suggest that the adenosine triphosphate-dependent potassium channel is downregulated in smooth muscle cells from the aortas of obese rats, which may contribute to the increase in blood pressure in these rats.
Fan
Li-Hong
LH
Department of Cardiology, The First Affiliated Hospital of Xi'an Jiaotong University School of Medicine, Xi'an, Shaanxi, China.
Tian
Hong-Yan
HY
Wang
Jun
J
Huo
Jian-Hua
JH
Hu
Zhi
Z
Ma
Ai-Qun
AQ
Cao
Yong-Xiao
YX
D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001011:Aorta / Q000378:metabolism*; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D015153:Blotting, Western; D015536:Down-Regulation; D005905:Glyburide / Q000494:pharmacology; D054086:KATP Channels; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D009765:Obesity / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D020110:Pinacidil / Q000494:pharmacology; D024661:Potassium Channels, Inwardly Rectifying / Q000235:genetics / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D064233:Sulfonylurea Receptors; D014665:Vasodilator Agents / Q000494:pharmacology
D018528:ATP-Binding Cassette Transporters; D054086:KATP Channels; D024661:Potassium Channels, Inwardly Rectifying; D011955:Receptors, Drug; D064233:Sulfonylurea Receptors; D014665:Vasodilator Agents; C092520:uK-ATP-1 potassium channel; D020110:Pinacidil; D005905:Glyburide