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DISCUSSION 



Olbrich: As you have shown, kidney infections very frequently occur 

 in mice. We don't know how long infection has been present before 

 amyloidosis appears. You work a fairly long time with a nephritic 

 animal. The pyelonephritis which you have shown is often seen in humans. 

 Rats or mice frequently get monilia — and other infections which last a 

 long time and lead to the development of amyloidosis. Do you know how 

 long the infection has been present? It is peculiar that the majority of 

 your animals suffer from "senile decrepitude"; I think these animals are 

 suffering from amyloidosis which is the result of a long-standing infection 

 of the kidneys. In other words you are experimenting with uraemic and 

 not normal animals. 



Muhlbock: We do not consider that the amyloidosis is a consequence 

 of an infection. We think it is a primary amyloidosis, and that it is 

 related to a special genetic constitution. Why should we have such 

 infections in one strain of mice and in another strain no infection at all ? 

 Moreover, in the kidneys amyloid infiltration comes first, and inflam- 

 mation is secondary. 



Olbrich: The only point is this: primary amyloidosis never appears 

 in the kidney in humans. 



Milhlbock: It may, exceptionally. The frequent renal localization in 

 mice is genetically conditioned. There are more of these peculiarities 

 in comparative gerontology: I have never seen arteriosclerosis in the 

 mouse and yet it is seen in the human being. We feel that senile amyl- 

 oidosis is the cause of death in these animals. 



Krohn: Amyloidosis is very unlikely to have occurred in the ovary 

 as a result of infection. 



Olbrich: You don't get it in ovaries. 



Krohn: Yes, you do in mice. 



Muhlbock: Yes, practically in all organs, but the distribution over 

 various organs is different in different strains. 



