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this article should be translated from the corresponding articles - german or spanish - they contain much more scientific information!
- Actually, this article is wrong. Think about it. If keratinocytes made a chemical upon DNA destruction called "thymidine dinucleotide" which caused the pituitary gland to make a hormone which triggers melanocytes to make melanosomes, releasing them along dendrites where they go to the top layer of the skin... What would stop the hormone from triggering an even tan? Nothing. There's something missing from the equation as it were. Otherwise, tan lines would not exist. And they do!
- You see:
- "Nitric Oxide and cGMP production is required for UVB-induced melanogenesis and that cGMP mediated its melanogenic effects mainly through the activation of cGMP-dependent kinase. " is how a tan is made. In laymen's terms what effectively happens is that UV-B triggers NO production which in turn triggers cGMP production which triggers melanocytes to undergo melanogenesis.--I'll bring the food 07:01, 2 January 2007 (UTC)
- I partiallly fixed it, but it requires much work, I don't have the time either, what a shame.--I'll bring the food 07:46, 2 January 2007 (UTC)
- My understanding was the the melanocortins are also produced in both a paracrine and autocrine manner (by keratinocytes and melanocytes respectively) in response to UV. This would explain tan lines. Rockpocket 08:20, 2 January 2007 (UTC)
Human differences calculation error - if each melanocyte is about 7 microns then a mm would contain 140 lined up side by side ( 1000/7 assuming average length). This means that a square mm would contain 19600 melanocytes for just a single layer. Have I missed something? Can you show where 1000 to 2000 per square mm comes from? House of Physics (talk) 21:08, 9 February 2012 (UTC)
- Sorry, didn't factor the 5 to 10% into calculations. That gives your 1000 to 2000. Not being a biologist, the diagram doesn't make it clear that the melanocytes are only the little dark bits that are separated by lots of other cells. Cheers House of Physics (talk) 21:26, 9 February 2012 (UTC)
Can anyone provide a citation for the average length of a melaocyte being 7 microns? I can't find any literature that confirms that measurement, and most of what I am finding seems to suggest they're much larger. 126.96.36.199 (talk) 14:52, 12 April 2013 (UTC)
I realize this is more than 2 years later, but just in case you're still wondering, yes, melanocytes are derived from neural crest ectoderm.