Uveal melanocytes do not respond to or express receptors for α-melanocyte-stimulating hormone
Uveal melanocytes do not respond to or express receptors for α-melanocyte-stimulating hormone
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DOI：
10.1167/iovs.06-0391
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发表时间：
2006-10-01
影响因子：
4.4
通讯作者：
Boissy, Raymond E.
中科院分区：
文献类型：
--
作者：
Li, Li;Hu, Dan-Ning;Boissy, Raymond E.
目的.而皮肤色素沉着增加后，暴露于紫外线（UV）照射，眼睛色素沉着不会。本研究旨在研究α-黑素细胞刺激激素（α-MSH），这被认为是在皮肤中的紫外线反应的介质，有任何作用，以发挥葡萄膜黑素细胞的证据。通过使用从成人尸体供体收获的眼睛培养来自脉络膜和虹膜的人葡萄膜黑素细胞，并通过北方印迹分析评估对α-MSH的生长和黑素生成反应以及α-MSH受体（MC 1-R）的表达。此外，通过免疫细胞化学法评估眼组织中α-MSH的表达。葡萄膜黑素细胞，不像体外皮肤黑素细胞，在0.1至100 μ M的剂量范围内，对α-MSH没有增殖刺激。此外，酪氨酸羟化酶、多巴氧化酶和酪氨酸酶、TRP-1和TRP-2的蛋白水平不受α-MSH的影响。通过北方印迹分析评估，与培养的葡萄膜黑素细胞中缺乏α-MSH反应相关的是缺乏α-MSH受体（MC 1-R）的表达。同样与皮肤相反，通过免疫细胞化学评估，色素眼组织缺乏α-MSH配体的表达。总之，眼部色素沉着似乎不受黑素细胞刺激激素的调节。
PURPOSE. Whereas cutaneous pigmentation increases after exposure to ultraviolet (UV) irradiation, ocular pigmentation does not. This study was designed to examine the evidence that alpha-melanocyte-stimulating hormone (alpha-MSH), which is thought to be the mediator of UV response in the skin, has any role to play in uveal melanocytes.METHODS. Human uveal melanocytes derived from the choroid and the iris were cultivated by using eyes harvested from adult cadaveric donors and were assessed by Northern blot analysis for growth and melanogenic response to alpha-MSH and expression of the receptor for alpha-MSH (MC1-R). In addition, expression of alpha-MSH was evaluated in ocular tissue by immunocytochemistry.RESULTS. Uveal melanocytes, unlike cutaneous melanocytes in vitro, exhibited no stimulation of proliferation in response to alpha-MSH at dosages ranging from 0.1 to 100 mu M. In addition, tyrosine hydroxylase, DOPA oxidase, and protein levels for tyrosinase, TRP-1, and TRP-2 were not influenced by alpha-MSH. Associated with the lack of alpha-MSH response in cultured uveal melanocytes was the absence of expression of the receptor for alpha-MSH (MC1-R), as assessed by Northern blot analysis. Also in contrast to the skin, pigmented ocular tissue lacked expression of the alpha-MSH ligand, as assessed by immunocytochemistry.CONCLUSIONS. In conclusion, ocular pigmentation does not appear to be regulated by melanocyte stimulating hormone.