ELEC ri{o\ M I ( .H( >S( ;< >I'Y 



cndotholial cell cytoplasm. In the capillary nicnihraiie and accumulation.s of a newly 



luniina tiiere were numerous rounded bodies formed material were most striking in the 



bordered by a sinfj;le membrane and contain- subacute and chronic cases. The large masses 



ing small cell organelles, mostly vacuoles, of this material seen in two cases of Lupus 



The authors concluded that these bodies Erythematosus correspond to the wire loops 



were parts of the cell cytoplasm ejected from obsen-ed with the light microscope, 

 the endothelial cell which was damaged by Cases of subacute and chronic glomeru- 



the inflammation. Later investigations have lonephritis with similar observations have 



shown that this may also be observed in also l)een reported by Spiro (1958, 1959). 

 healthy humans and animals, but in the au- Judging from these reports glomerulone- 



thors' opinion the process was markedly in- phritis is primarily a disease of the vascular 



creased in the case of glomerulonephritis, endothelium in the glomeruli with a swelling 



There were no definite changes in the base- and vacuolization of the cytoplasm of these 



ment membrane or in the epithelial cells. cells followed by a precipitation of a foreign 



Farquhar da/. (1957a) have described two material in the basement membrane and 



cases of acute, two of subacute and three of probably also in the endothelial cell cyto- 



chronic glomerulonephritis. They observed plasm. The basement membrane is thick- 



in the acute stage of the disease a prolifera- ened and subseciuently the epithelial cells 



tion and swelling of the endothelial cells and are also destroyed along with the whole glo- 



later of the epithelial cells in the glomeruli, merulus, as is well known from light micro- 



The epithelial foot process organization ap- scopic studies. From the following sections it 



peared normal in contrast to the observa- will be seen that similar changes also occur 



tions in nephrosis (see below). The basement in other renal diseases, 

 membranes were thickened and large masses 



of a basement membrane-like material was Morphological Changes Associated with 

 accumulated probably inside endothelial the Nephrotic Syndrome 



cells. They concluded that this material was Experimental Nephrosis. The glomeru- 



produced by the endothelial cells. In the later lar lesions in aminonucleoside nephrosis in 



stages of the disease the capillaries were de- rats have been studied by Feldman and 



stroyed and replaced by masses of the base- Fisher (1959), Harkin and Recant (1959), 



ment membrane-like substance. Collagen and Vernier et al. (1958, 1959). Daily subcu- 



fibrils were not observed. taneous injections of small amounts of this 



Similar alterations were seen by the same substance evoked proteinuria in seven days, 

 authors in three cases of Lupus Erythema- Simultaneously a swelling and vacuolization 

 tosus. The thickening of the basement mem- of the capillary epithelial cells were observed, 

 brane was more pronounced than in glomer- The foot process structure was dissolved and 

 ulonephritis. Nodular accumulations of a the outer surface of the basement membrane 

 basement membrane-like substance were also covered by a nearly continuous layer of epi- 

 observed in the endothelial cells. Collagen thelial cell cytoplasm. After prolonged treat- 

 fibrils were not found. These observations ment there was also a diffuse thickening of 

 were confirmed by Putois (1959). the basement membrane and a precipitation 



In a subsequent paper by Vernier et al. of a foreign material on the endothelial side 



(1958a) 11 cases of glomerulonephritis and of the membrane (Vernier e^ ai.). There were 



four cases of Lupus Erythematosus in chil- no changes of the endothelial cells. In the 



dren were described. Proliferative changes in tubular epithelium a .swelling of the mito- 



the endothelium dominated in the acute chondria and a number of large vacuoles in 



cases whereas the thickening of the basement the cytoplasm were observed. 



208 



