![Figure 2. Effects of ACh on the membrane potential in the presence of various extracellular Potassium sup + concentrations in the endothelium-intact strips. (A) Typical examples of the ACh (0.03–10 micro Meter)-induced hyperpolarization in the presence of 3.6 and 5.9 mM extracellular [Potassium sup +]. (B) The closed and open circles show the effects of ACh on the resting membrane potential in the presence of 3.6 and 5.9 mM extracellular [Potassium sup +], respectively. Data are mean plus/minus SD (n = 5–11, four to five preparations). ACh = acetylcholine, [K sup +]oextracellular Potassium sup + concentration. #Significantly different (P < 0.05) from the membrane potential before the application of ACh within each group. *Significantly different (P < 0.05) from the ACh-induced hyperpolarization in the presence of 5.9 mM extracellular Potassium sup + at each concentration. (C) The effects of ACh (3 micro Meter) on the membrane potential in the presence of various extracellular Potassium sup + concentrations. The closed circles show the effects of ACh on the membrane potential in the presence of various extracellular Potassium sup + concentrations (1.2–77 mM), whereas the open circles show the control membrane potential in the absence of ACh. The dotted line indicates the equilibrium potential for Potassium sup + calculated from Nernst's equation (35 degrees Celsius), assuming that the intracellular Potassium sup + concentration is 140 mM. Data are mean plus/minus SD (n = 6–25, three to five preparations). [K sup +]oextracellular Potassium sup + concentration. *Significantly different (P < 0.05) from the control membrane potential at each concentration.](https://asa2.silverchair-cdn.com/asa2/content_public/journal/anesthesiology/82/1/10.1097_00000542-199501000-00024/2/24ff2.png?Expires=1716615601&Signature=S9uP9ZlCnHez6aEp3r7Gz1Dz0e1DGXiGcvlRukU2r~DMtLhTaTgeSNnB70qEHQJZEW~OLAmHhqeuKqbwhu~-fcWOFDI-7ycbKVAxH9sbNxBRAHoMI2cP5hs6GCCM5uls8uQJoHt5VU9-yngo9k2xI2UAfBFKGOSVlpGwiakbnLmiSbCCeDaJeXO-EDqaD9etQW0TGcq6o9xjNBOnisKf9t8mq3b2znTnbkC2UmG2KmgugjhwINZutcr8LlekaMJNffJ~aSdoJKcuETWT5~jjVgtNVyTmjCPQsPzxwwbZiOd-Jev6Gb6Yaoq5mcnP5yDCwKSE2x9H8o9FY8MTFgCm0g__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Figure 2. Effects of ACh on the membrane potential in the presence of various extracellular Potassium sup + concentrations in the endothelium-intact strips. (A) Typical examples of the ACh (0.03–10 micro Meter)-induced hyperpolarization in the presence of 3.6 and 5.9 mM extracellular [Potassium sup +]. (B) The closed and open circles show the effects of ACh on the resting membrane potential in the presence of 3.6 and 5.9 mM extracellular [Potassium sup +], respectively. Data are mean plus/minus SD (n = 5–11, four to five preparations). ACh = acetylcholine, [K sup +]oextracellular Potassium sup + concentration. #Significantly different (P < 0.05) from the membrane potential before the application of ACh within each group. *Significantly different (P < 0.05) from the ACh-induced hyperpolarization in the presence of 5.9 mM extracellular Potassium sup + at each concentration. (C) The effects of ACh (3 micro Meter) on the membrane potential in the presence of various extracellular Potassium sup + concentrations. The closed circles show the effects of ACh on the membrane potential in the presence of various extracellular Potassium sup + concentrations (1.2–77 mM), whereas the open circles show the control membrane potential in the absence of ACh. The dotted line indicates the equilibrium potential for Potassium sup + calculated from Nernst's equation (35 degrees Celsius), assuming that the intracellular Potassium sup + concentration is 140 mM. Data are mean plus/minus SD (n = 6–25, three to five preparations). [K sup +]oextracellular Potassium sup + concentration. *Significantly different (P < 0.05) from the control membrane potential at each concentration.
