Study on calcium-activated potassium channel of mesentery artery smooth muscle cells of hypertension patients / 中国应用生理学杂志

ABSTRACT

<p><b>AIM</b>To study the functional activity of K(cA) on human mesenteric artery smooth muscle cells (SMC) from essential hypertension (EH) patients.</p><p><b>METHODS</b>Patch clamp technique with Inside-out mode was used for recording channel activity.</p><p><b>RESULTS</b>(1) K(CA) from human mesenteric artery SMC was voltage dependent. Single channel conductance was 191.4 pS and 197.7 pS in EH group and normal group respectively. The channel activity was blocked by TEA in cytoplastic side. (2) With the increasing of Ca2+ concentration in the bath solution (fron 0 to 10(-8), 10(-7), 5 x 10(-7), 10(-6) mol/L), the K(Ca) channel open probability (Po) of two groups were increased, Po of EH group increased from 0.016 to 0.023, 0.031, 0.0153, 0.094, Po of normal group increased from 0.004 to 0.023, 0.041, 0.072, 0.184. The mean open time lengthened and the mean close time shortened. (3) Po of K(Ca) of EH group was higher than that of normal group when Ca2+ concentration was 0, but it was equal with or lower than normal group at the other Ca2+ concentrations.</p><p><b>CONCLUSION</b>K(Ca) of mesenteric artery SMC from EH group has a lower Ca2+ sensitivity than that of normal person. This might be an active factor for the onset of EH.</p>