Purchase this article with an account.
Li Li, Dan-Ning Hu, Huiquan Zhao, Steven A. McCormick, James J. Nordlund, Raymond E. Boissy; Uveal Melanocytes Do Not Respond To or Express Receptors for α-Melanocyte-Stimulating Hormone. Invest. Ophthalmol. Vis. Sci. 2006;47(10):4507-4512. doi: 10.1167/iovs.06-0391.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
purpose. Whereas cutaneous pigmentation increases after exposure to ultraviolet (UV) irradiation, ocular pigmentation does not. This study was designed to examine the evidence that α-melanocyte-stimulating hormone (α-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 α-MSH and expression of the receptor for α-MSH (MC1-R). In addition, expression of α-MSH was evaluated in ocular tissue by immunocytochemistry.
results. Uveal melanocytes, unlike cutaneous melanocytes in vitro, exhibited no stimulation of proliferation in response to α-MSH at dosages ranging from 0.1 to 100 μM. In addition, tyrosine hydroxylase, DOPA oxidase, and protein levels for tyrosinase, TRP-1, and TRP-2 were not influenced by α-MSH. Associated with the lack of α-MSH response in cultured uveal melanocytes was the absence of expression of the receptor for α-MSH (MC1-R), as assessed by Northern blot analysis. Also in contrast to the skin, pigmented ocular tissue lacked expression of the α-MSH ligand, as assessed by immunocytochemistry.
conclusions. In conclusion, ocular pigmentation does not appear to be regulated by melanocyte stimulating hormone.
This PDF is available to Subscribers Only