FUNCTIONAL SIGNIFICANCE — MITOCHONDRIA 439 



The single observations of Policarcl ('12, p. 229) on the tem- 

 perature solubihty of mitochondria are, perhaps, not without 

 significance. He found that exposure to a temperature of from 

 47-50°C. for 30 minutes dissolved the mitochondria in kidney 

 cells without affecting the appearance of the nuclei. It is well 

 within the bounds of possibility that a prolonged or intermittent 

 temperature of say 41°C. (105.8°F.), as in a high fever, may 

 bring about a solution or chemical alteration of mitochondria 

 in some or other cells of the body. This is, at any rate, an 

 interesting thought in connection with Welch's ('88, p. 403) 

 belief that fatty degeneration of the heart muscle is in some way 

 associated with high fevers for we have evidence that mitochon- 

 dria are chemically related to the phospholipins. 



Two interesting hypotheses have been advanced on the sup- 

 position that mitochondria liberate chohn, which is quite likely 

 since on hydrolytic dissociation lecithin, a typical phospholipin, 

 yields cholin (Mathews '15, p. 91) : 



C42H84NPO9 + 4H2O = Cl8H3402 + ClsHjoO., + CsHsO,, + H3PO4 + CsH.sNO, 



Macklin ('16) has found that they are particularly abundant 

 in the constriction between the two parts of nuclei dividing 

 by amitosis and advances the view that they may be giving 

 off cholin, which, if Robertson's supposition is correct, may 

 lower the surface tension locally and thus facilitate the nuclear 

 constriction. Cowdry ('16) has made the suggestion that 

 cholin may be set free in the nervous system through the dis- 

 integration of mitochondria, and that, inasmuch as organic 

 diseases of the nervous system can be separated from functional 

 neuroses by the formation of cholin in the one and not in the 

 other (Halliburton '07, p. 74), it is possible that a study of mito- 

 chondria may afford a cytological basis of distinction between 

 these two groups of nervous diseases. 



Thus far no account of mitochondria in acidosis has appeared. 

 Now it is common knowledge that mitochondria are very sen- 

 sitive to acids. It is also well known that one of the first mani- 

 festations of acidosis is a marked inhibition of the respiratory 

 oxidation of the cell (jMathews' 15, p. 247). If there is any- 



THE AMERICAN JOIRNAL OF ANATOMY, VOL. 19, NO. 3 



