106 General Discussion 



gross scale — ^a square foot of skin at a time — ^aiid obtained slightly 

 higher results than those we have quoted earlier. But whichever way 

 you look at it, be it by weight, volume or crude analysis, it would seem 

 that at the most there is not more than 5 per cent, and probably less, 

 elastin in dermal tissue. 



The other point is one which I thought we had proved, but Dr. Lansing 

 disagrees with us: this question of senile elastosis. The elastic staining 

 material is not elastic tissue, it is altered collagen — ^considerably altered, 

 but still collagen. This answers Bean's point, I think, because the 

 blood vessels are less well supported and they are very vulnerable to 

 trauma. The extraordinary thing is that it increases with age, it is 

 present in about 2-3 per cent of the population at the age of sixty, and 

 in 25 per cent of all we have been able to examine at ninety; there is a 

 linear relationship. With it goes scarring, tendency to haemorrhage and 

 so on, but it is definitely altered collagen. Dr. von Albertini would agree 

 that it is a totally different collagen degradation product from that 

 wliich you get in the rheumatic nodules, both chemically and in its 

 resistance to enzyme action. The lesion is usually said to be due to 

 exposure, but we had one old lady of ninety who for various reasons had 

 lived in hospital since the age of seven, and she had this change in a very 

 striking degree — -where she got the sunlight in a hospital in Leeds, 

 I do not know! 



Lansing: Well, apropos of your first point, there certainly is no issue 

 on which to cross swords. I don't believe that there is a rich bed of 

 elastic tissue in normal skin, and indeed the illustration I showed of the 

 abdominal surface showed a remarkable lack of elastic elements, at 

 least in the pars papillaris; there was rather a coarse net deep in the 

 reticular portion of the skin, but I think we would all agree that there is 

 probably less than 1 per cent extractable elastin in skin on a dry weight 

 basis. 



We differ very sharply as to what this material is that we see in 

 senile elastosis. This may be a matter of semantics or one of simple 

 definition, but the fact is that this peculiar bed of material appears in the 

 pars papillaris of human skin, usually but not necessarily in exposed 

 portions of the body. This material stains like elastic tissue. We have 

 very few criteria for defining elastic tissue; the best ones we have depend 

 on tinctorial reactions. Affinity for orcein is rather specific, and this 

 material stains rather well with orcein. The resorcin-fuchsin reagent 

 stains elastic tissue quite specifically, it does not stain collagen, and this 

 material in senile elastosis takes the resorcin-fuchsin dye. Similarly the 

 Verhoeff's dye which I illustrated here, is a little less specific but stains 

 effectively. So, tinctorially, this stuff behaves like elastic tissue. I 

 pointed out that the elastase which is ratiier generally specific for 

 elastic tissue, with one rather recent exception (the heat denatured 

 collagen), responds to it, but within an hour after exposure to elastase 

 at a pH of 9 • the material that normally stains like elastic tissue in 

 senile elastosis disappears entirely, it does not take up any of the elastic 

 tissue dyes. And lastly, that material when exposed to the aniline blue or 

 any of the Mallory reagents for collagen is entirely negative. 



