고혈압 및 정상혈압백서의 대동맥 평활근 세포에서 ATP-sensitive K^+ Channel에 대한 Cromakalim의 영향 = ATP-sensitive K^+ channel in aortic smooth muscle cells from normotensive and spontaneously hypertensive rats

다국어 초록 (Multilingual Abstract)

To determine wherther the properties of ATP-sensitive K^+ channel (K_ATP channel) in aortic smooth muscle cells from spontaneously hypertensive rats are altered of not, the effect of a K^+ channel opener, cromakalim, on membrane currents in aortic smooth muscle cells from spontaneously hypertensive rate (SHR) and Wista-Kyoto rats (WKY) were compared, using a patch-clamp technique.
1. The internal and external K^+ were 140 and 60 mM, respectively. The currents were recorded at -70mV. The inward current was evoked by cromakalim and this current was inhibited by glibenclamide.
2. The cromakalim-evoked current was time-independent and voltage-insensitive.
3. The reversal potential of cromakalim-evoked current depended on external K^+ concentration, and this current was reversed at near K^+ equilibrium potential.
4. The cromakalim-evoked current was reduced when the intracellular ATP concentration was raised from 0.1mM to 3 mM.
5. In SHR, crmakalim-evoked current, normalized by cell capacitance, was not changed when compared to WKY.
From the above results, it is suggested that cromakalim-evoked current was carried throuhg K_ATP channel and the function of cromakalim on K_ATP channel in aortic smooth muscle cells of SHR is not impaired when compared to WKY cells