Volume-dependent ATP-conductive large-conductance anion channel as a pathway for swelling-induced ATP release.
Volume-dependent ATP-conductive large-conductance anion channel as a pathway for swelling-induced ATP release.
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DOI：
10.1085/jgp.118.3.251
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发表时间：
2001-09
期刊：
影响因子：
--
通讯作者：
Okada Y
中科院分区：
文献类型：
--
作者：
Sabirov RZ;Dutta AK;Okada Y
在小鼠乳腺C127 i细胞中，在全细胞钳夹过程中，当根皮素敏感的体积激活外向整流Cl−通道被消除时，渗透性细胞肿胀激活了阴离子通道电流。该电流在大于约±25 mV的正电压和负电压下表现出时间依赖性失活。全细胞电流对阴离子具有选择性，对Gd ~（3+）敏感。在细胞上贴片中，低渗激发后出现单通道事件，滞后期为± 15分钟。在等渗条件下，细胞附着的补丁是沉默的，但补丁切除导致激活的电流，包括多个大电导单一的步骤。电流显示电压和时间依赖性失活类似的全细胞电流。电压依赖性激活曲线呈钟形，最大开放概率为-20至0 mV。由内而外的贴片中的通道具有单位电导率为2400 pS，线性电流-电压关系和阴离子选择性。细胞外ATP抑制外向（而非内向）单通道电导，IC 50为12.3 mM，电距离（δ）为0.47，而细胞内ATP抑制内向（而非外向）电导，IC 50为12.9 mM，δ为0.40。尽管开放通道被ATP阻断，但通道是ATP传导的，PATP/PCl为0.09。单通道活性对Gd 3+、SITS和NPPB敏感，但对根皮素、尼氟灭酸和格列本脲不敏感。在肿胀诱导的ATP释放中发现了相同的药理学模式。因此，可以得出结论，体积和电压依赖性ATP传导大电导阴离子通道作为一个导电途径肿胀诱导的ATP释放在C127 i细胞。
In mouse mammary C127i cells, during whole-cell clamp, osmotic cell swelling activated an anion channel current, when the phloretin-sensitive, volume-activated outwardly rectifying Cl− channel was eliminated. This current exhibited time-dependent inactivation at positive and negative voltages greater than around ±25 mV. The whole-cell current was selective for anions and sensitive to Gd3+. In on-cell patches, single-channel events appeared with a lag period of ∼15 min after a hypotonic challenge. Under isotonic conditions, cell-attached patches were silent, but patch excision led to activation of currents that consisted of multiple large-conductance unitary steps. The current displayed voltage- and time-dependent inactivation similar to that of whole-cell current. Voltage-dependent activation profile was bell-shaped with the maximum open probability at −20 to 0 mV. The channel in inside-out patches had the unitary conductance of ∼400 pS, a linear current-voltage relationship, and anion selectivity. The outward (but not inward) single-channel conductance was suppressed by extracellular ATP with an IC50 of 12.3 mM and an electric distance (δ) of 0.47, whereas the inward (but not outward) conductance was inhibited by intracellular ATP with an IC50 of 12.9 mM and δ of 0.40. Despite the open channel block by ATP, the channel was ATP-conductive with PATP/PCl of 0.09. The single-channel activity was sensitive to Gd3+, SITS, and NPPB, but insensitive to phloretin, niflumic acid, and glibenclamide. The same pharmacological pattern was found in swelling-induced ATP release. Thus, it is concluded that the volume- and voltage-dependent ATP-conductive large-conductance anion channel serves as a conductive pathway for the swelling-induced ATP release in C127i cells.
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影响因子：
3.8
作者：
Hazama, A;Shimizu, T;Okada, Y
通讯作者：
Okada, Y
囊性纤维化跨膜电导调节剂相关的ATP释放由氯化物传感器控制。
影响因子：
7.8
作者：
Jiang, Q;Mak, D;Devidas, S;Schwiebert, E M;Bragin, A;Zhang, Y;Skach, W R;Guggino, W B;Foskett, J K;Engelhardt, J F
通讯作者：
Engelhardt, J F
DOI：
10.1152/ajpcell.1997.272.2.c466
发表时间：
1997-02-01
影响因子：
5.5
作者：
Cantiello, HF;Jackson, GR;Ausiello, DA
通讯作者：
Ausiello, DA
DOI：
10.1152/ajpcell.1996.271.5.c1527
发表时间：
1996-11-01
影响因子：
5.5
作者：
Bosch, I;Jackson, GR;Cantiello, HF
通讯作者：
Cantiello, HF
影响因子：
3.5
作者：
JAKOB, C;GOTZ, H;HILSCHMANN, N
通讯作者：
HILSCHMANN, N