42 The Chemistry of the Injured Cell 



ceeded the mechanism of droplet formation is brought into play 

 and the cell assumes an appearance indistinguishable from cloudy 

 swelling. Similar changes, often termed hyaline change or degenera- 

 tion, are known to occur in human subjects during the excretion 

 of haemoglobin, Bence-Jones protein and myeloma proteins, and 

 indeed in any heavy proteinuria due for example to glomerulone- 

 phritis. 



Hypertrophy of Cells 



When portion of a rat's liver is removed the part left behind 

 hypertrophies and inclusion bodies appear within the rapidly re- 

 generating liver cells. These are mainly albuminous in nature. A 

 critical liver mass and plasma albumin must be reached before 

 they become apparent in the liver cells, and their development is 

 prevented by pre-operative starvation which lowers the plasma 

 albumin level. Feeding with glucose will do the same (Doniach 

 and Weinbren, 1952) . The basophilic bodies of liver cells that we 

 know to be masses of ribonucleoprotein are greatly increased during 

 gestation (Clavert and Assenmacher, 1952) . A similar increase of 

 RNA and also of DNA occurs at an early period of compensatory 

 hypertrophy in the liver along with increase in activity of a number 

 of cell enzymes, especially esterases and phosphatases. Such facts 

 suggest an increase in protein synthesis without necessarily a poten- 

 tiation of all of the cellular biochemical activities correlated with 

 it (Pileri et al., 1957) . No doubt a similar explanation holds for the 

 liver cell hypertrophy of Waldenstrom's macroglobulinaemia with 

 its cytoplasmic increase of RNA (Wuketich and Siegmund, 1958). 

 Nucleic acids are increased, too, in hypertrophying renal cells; here, 

 too, RNA is affected more than DNA (Vegni, 1953; Fautrey et al., 

 1955) . Increase of protein N is remarkable at the height of hyper- 

 trophy, especially in the microsome fraction of the cells (Dianzani 

 and Biaggini, 1954) . 



ACTION OF HORMONES ON CELL PROTEINS 



When the pituitary gland is removed from the rat the RNA 

 content of the mitochondrial fraction of the liver decreases and the 



