6i6 



REGENERATION AND GROWTH 



TABLE 10 



EVIDENCE FOR A DECREASE IN AEROBIC RESPIRATION DURING EARLY STAGES 



OF REGENERATION 



Nature of evidence 



Aiaterial 



Reference 



Decrease in O2 

 consumption 



Hydra Ajsupiet, 1937 



Tnbidaria Barth, 1937; Goldin and Barth, 1941 



Turbellaria Lovtrup, 1953; Von Levetzow, 1939 



Tubifex Collier, 1947 



axolotl Ryvkina, 1945 



liver Van Bekkum and Peters, 1951 



Decrease in concentration 

 of enzymes concerned in 

 aerobic respiration 



mammalian 

 iver 



, ma 

 \ 1 



Novikoff and Potter, 1948; Rosen- 



mammalian 

 nerve 



' thai, et al., 1951 ; Harkness, 1952; 



' Tsuboi, et al., 1954 



I Bodian, 1947; Howe and Flexner, 



. 1947; 



' Howe and Mellors, 1948 



Retardation of regeneration mammalian 

 by cytochrome c liver 



Drabkin et al., 1950 



(Williamson and Fromm, 1955). Again the sulphuric acid of mucopolysaccharides 

 (Kent and Whitehouse, 1955) possibly may be derived from the sulphur-contain- 

 ing amino-acids, inorganic sulphates being little absorbed from the gut. After 

 laparotomy and after X-irradiation there is an inverse correlation between plas- 

 ma-SH and plasma-polysaccharide concentrations (Schacter et at., 1952), which 

 lends colour to this view. Methionine may be important mainly as a source of 

 cysteine and of these other svilphur-compounds (Williamson and Fromm, 1955), 

 though Bertolani et al. (1954) find evidence that its action on regeneration is cor- 

 related with its well-known lipotropic action (McHenry and Patterson, 1944). 



There is little doubt, however, that the SH-compounds are the most important 

 sulphur-compounds here. They have key-functions at almost every stage of regener- 

 ation. GSH is highly concentrated in the adrenal cortex (Sayers, 1950), and con- 

 trols the action of corticotropin (Anon., 1955). Possibly for this reason stress causes 

 a temporary depletion of SH-compounds from the liver (Beck and Linkenheimer, 

 1952), though during regeneration these may be mobilised also for specific use. 

 Further, cortisone inhibits the uptake of sulphur into granulation-tissue (Layton, 



