Finkle T J, Grover A K
Department of Neurosciences, McMaster University Health Sciences Centre, Hamilton, Ontario, Canada.
Biochem Biophys Res Commun. 1988 Feb 29;151(1):473-9. doi: 10.1016/0006-291x(88)90617-1.
Single smooth muscle cells were isolated from circular muscle of the canine gastric corpus by collagenase incubation. Cytoplasmic pH (pHi) of these cells was measured fluorometrically using the trapped dye 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein. Cells were examined for their Na+/H+ exchange activity after intracellular acidification. Cells acid-loaded by propionate exposure, the NH4+ prepulse technique or suspension in a Na+-depleted medium regained almost normal pHi upon exposure to a Na+ medium. The Na+-dependent alkalinization was amiloride sensitive. As well, addition of amiloride to cells suspended in a Na+ medium caused a concurrent decrease in pHi. The study indicates that a Na+/H+ antiport is present in these smooth muscle cells.
通过胶原酶孵育从犬胃体环行肌中分离出单个平滑肌细胞。使用捕获染料2',7'-双（羧乙基）-5,6-羧基荧光素通过荧光法测量这些细胞的细胞质pH（pHi）。在细胞内酸化后检测细胞的Na+/H+交换活性。通过丙酸盐暴露、NH4+预脉冲技术或悬浮在无钠培养基中进行酸加载的细胞，在暴露于钠培养基后恢复到几乎正常的pHi。钠依赖性碱化对氨氯地平敏感。同样，向悬浮在钠培养基中的细胞中添加氨氯地平会导致pHi同时降低。该研究表明这些平滑肌细胞中存在Na+/H+反向转运体。
