1910.] 



The Origin of Osmotic Effects. 



601 



One other case we may refer to — that afforded by the fell disease. 

 Diabetes. It is apparently impossible to account for the di8posal|of the 

 whole of the sugar derived from the digestion of food on the assumption that 

 it all passes as such directly into the circulation, the amount present in 

 normal blood being always very small and subject to but slight variation. 

 The veteran student of this subject, Pavy, has suggested* that as dextrose 

 passes from the digestive tract into the lymphatic system it becomes 

 attached to the lymphocytes ; by these it is carried into the blood stream in 

 a hidden form, ready to be liberated whenever and wherever required. The 

 explanation is entirely rational. Assuming it to be correct, the association 

 of dextrose with the lymphocytes must be dependent on a certain high 

 minimum concentration of the lymph ; if anything occurred to reduce the 

 concentration below this minimum, the synthetic action would be inhibited 

 and the dextrose would enter as such into the circulation. It is conceivable 

 that the disease is conditioned by the presence of some hormone which 

 determines a reduction in the concentration of the lymphatic fluid. It is 

 at least worth while to study the problem from this point of view. 



It is to be supposed that hormones exercise a determining influence in 

 regulating metabolism in plants as well as in animals.f 



Obviously, there are many directions in which our hypothesis may be 

 usefully applied. Stated briefly, it is that substances generally which are not 

 attractive to water when introduced into the living cell exercise stimulative 

 effects which are primarily mechanical, as the effects are produced by the inter- 

 position of the hormone molecules l^etween the molecules of liquid in the cell ; 

 as such interposition, however, at once alters the osmotic state by promoting 

 dissociative chemical change in the water in the direction (HgO)! ^ aiHgO, 

 the activity of the medium is raised and the equilibrium disturbed, so 

 that an influx of water from other regions sets in. It may be that often 

 the mere dilution thus effected is determinative of change. In some cases 

 contact becomes established between hydrolyte and hydrolyst, by the 

 former passing to the surface at which the hormone is at first effective 

 and which happens to be the seat of the hydrolyst ; degenerative changes are 

 thereby set up which tend to increase in intensity, as the products of change 

 in turn exercise a similar stimulative influence and enzymes are gradually 

 set free which can attack the various hydrolytes stored in the cell.lf Under 



* 'The Lancet,' November 21 and 28, December 12, 1908. 



t This section is perforce omitted to shorten the communication. 



\ The experiments made by Vernon {cf. ' Intracellular Enzymes,' London, John Murray, 

 1908) are of special interest in this connection. According to this observer, the 

 mammalian heart or kidney may be perfused with the saline solution used by 



