Kinetics of tyramine transport and permeation across chromaffin-vesicle membranes.
Kinetics of tyramine transport and permeation across chromaffin-vesicle membranes.
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酪胺跨嗜铬囊泡膜转运和渗透的动力学。
DOI：
10.1021/bi00304a020
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发表时间：
1984
期刊：
影响因子：
2.9
通讯作者：
D. Njus
中科院分区：
文献类型：
--
作者：
J. Knoth;J. Peabody;P. Huettl;D. Njus
酪胺通过利血平不敏感机制渗透亲铬颗粒膜。该速率是不饱和的，并随pH值增加，表明未质子化形式的胺的渗透。利血平不敏感的多巴胺摄取至少慢10倍，与多巴胺的亲脂性较低一致。多巴胺通过可饱和、利血平敏感、质子连接的机制转运到亲铬颗粒膜囊泡中。酪胺抑制多巴胺转运，Ki为5-10 μ M。酪胺的积累不如多巴胺，因为内向转运与外向渗透相反。然而，利血平敏感酪胺运输的速度可以从酪胺积累的稳态水平和渗透率推导出来。酪胺转运的Vmax约为多巴胺转运值的三分之一。因此，两个芳香族羟基不需要单胺运输，但需要有效的积累和储存。
Tyramine permeates chromaffin-granule membranes via a reserpine-insensitive mechanism. The rate is unsaturable and increases with pH, indicating permeation of the unprotonated form of the amine. Reserpine-insensitive dopamine uptake is at least 10 times slower, consistent with dopamine's lesser lipophilicity. Dopamine is transported into chromaffin-granule membrane vesicles via a saturable, reserpine-sensitive, proton-linked mechanism. Tyramine inhibits dopamine transport with a Ki of 5-10 microM. Tyramine is not accumulated nearly as well as dopamine because inward transport is opposed by outward permeation. Nevertheless, the velocity of reserpine-sensitive tyramine transport can be deduced from the steady-state level of tyramine accumulation and the rate of permeation. Vmax for tyramine transport is about one-third of the value for dopamine transport. Therefore, two aromatic hydroxyls are not needed for monoamine transport but are required for efficient accumulation and storage.
酪胺、间氨醇和异丙肾上腺素在分离的嗜铬颗粒和鬼影中积累的机制。
影响因子：
5.8
作者：
Johnson,RG;Carty,SE;Hayflick,S;Scarpa,A
通讯作者：
Scarpa,A
质子：嗜铬鬼中生物胺主动运输过程中的底物化学计量。
DOI：
--
发表时间：
1981
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Johnson,RG;Carty,SE;Scarpa,A
通讯作者：
Scarpa,A