Inoue K, Nakazawa K, Fujimori K, Takanaka A
Division of Pharmacology, National Institute of Hygienic Sciences, Tokyo, Japan.
Neurosci Lett. 1989 Dec 4;106(3):294-9. doi: 10.1016/0304-3940(89)90179-1.
Characteristics of extracellular ATP-stimulated norepinephrine (NE) secretion were investigated by the batch method in relation to membrane current measured with the whole cell voltage-clamp technique. Extracellular ATP stimulated [3H]NE secretion from PC12 cells in a concentration range from 10 microM to 1 mM. The maximal effect of ATP was about 5 times larger than that of nicotine. ATP-stimulated secretion was extracellular Ca-dependent, but it was not inhibited by the Ca-channel blockers, cadmium (300 microM) or nicardipine (10 microM). Extracellular ATP activated an inward current in PC12 cells and the peak amplitude of the current was about 5 times larger than that activated by nicotine. These findings suggest that extracellular ATP activates receptor-operated channels and causes NE secretion.
采用批量法研究了细胞外ATP刺激去甲肾上腺素（NE）分泌的特性，并与用全细胞膜片钳技术测量的膜电流相关联。细胞外ATP在10微摩尔至1毫摩尔的浓度范围内刺激PC12细胞分泌[3H]NE。ATP的最大效应比尼古丁大5倍左右。ATP刺激的分泌依赖细胞外钙，但不受钙通道阻滞剂镉（300微摩尔）或尼卡地平（10微摩尔）的抑制。细胞外ATP激活了PC12细胞中的内向电流，电流的峰值幅度比尼古丁激活的电流大5倍左右。这些发现表明，细胞外ATP激活受体操纵通道并导致NE分泌。
