Electrical responses of aortic endotheliumin spontaneously-hypertensive rats
A.I. Bondarenko V.F. Sagach
A.A.Bogomoletz Institute of PhysiologyNational Academy of Science of Ukraine, Kiev
Abstract
Endothelium-dependent relaxation is known to be
depressed in arteries of SHR. We studied acetylcholine
(Ach) -induced electrical responses of intact aortic
endothelial cells from WKY rats and SHR using perforated patch-clamp method.
Resting Em averaged -44,3±1,1 mV and -35,2±1,2 mV for WKY and SHR,
respectively. Application of K+ free solution depolarized
endothelium by 11,0±0,7 mV and 7,5±1,3 mV (р<0,05)
for WKY and SHR, respectively, showing inhibition
of endothelial electrogenic Na+/K+ pump in SHR. The
amplitude of Ach-induced hyperpolarization for WKY
and SHR was 19±1 mV and 25±1 mV, respectively.
However, the rate of its recovery was different within
particular preparation taken from SHR whereas it was
very similar within particular preparation from WKY
rats, showing alterations in intercellular signaling in endothelium of SHR.
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