654 D I. \ BETES 



]>i('lMHi(lcianco <if iiiHlissociali'd nuili'ciiles in dynamic ('(|uilil)riiim. witli a very 

 minute quantity of dissociated methylene CIIiOH ^ C'lL + ILO. Tlie primary 

 efi'ect of alkali (KOH) is to form a salt, ('H3 — 0\\ (or K-metliy!ate) , wliioli being 

 liiiilily dissociable breaks down to give CH^ and KOH. Tlie proportion of free 



mi'tliylene is thereby enormously increased, ^^'hat tlien befalls the metiiylene 

 will depend on the amount of oxygen present and on the various other factors 

 which enter into the conditions of tlie experiment. These general principles are 

 applicable directly to the j)olyatomic alcohols — the hexoses and other sugar.s — as 

 shown on preceding j)age. 



In the presence of sullicient oxygen the methylene particle takes on oxygen 

 to form first an osone. In the absence of oxygen it vmdergoes intramolecular 

 rearrangements, the details of which need not here be entered into. It is these 

 wliich gives rise to the 6 carbon acids known as the saccharines or saccharinic 

 acids. 



GALACTOSE 



A normal individual weighino- 75 kilos may eat about 50 grams of 

 galactose and show but a trace of melituria. ]\Iore than this is likely 

 to cause the presence of measurable amotnits of galactose in tlie 

 urine, the alimentary tolerance limit for this sugar being therefore 

 about 0.6 to 0.8 grams per kilogram of body weight. AVe have no 

 direct data concerning the time within which 50 grams of galactose 

 are absorbed by a man of average weight. When given intravenously 

 at uniform rates, unchanged galactose appears in the urine of dogs 

 receiving slightly more than 0.1 gm. per kilo per hour. The tolerance 

 for galactose appears to be lessened in phos])h()rus poisoning and in 

 many other conditions which cause apparent parenchymatous changes 

 in the liver, so that after administration of 50 grams of galactose by 

 mouth, as much as 10 to 12 grams may be excreted in the urine. 

 (Bauer.) On the other hand, ligation of the common duct does not 

 lessen the tolerance for galactose in rabbits (Reiss and Jehn, Hierose) 

 so that the lowered tolerance following phosj^horus administration ap- 

 l)eai's to be indepentlent of the disturbed biliary function. Infants 

 suffering from gastro-enteritis may show" alimentary lactosuria, and 

 along with the lactose some of its constituent galactose may apear in 

 the urine. The question thus naturally arises as to whether the lowered 

 tolerance for galactose in phos])horus poisoning and other liver dis- 

 eases may not be due to an increased permeability of the intestinal wall, 

 or to changes elsewhere in the body besides the liver. Worner found 

 that galactose injected directly into the portal vein Avas handled by 

 liealthy and phosphorized rabbits in the same relative prop(n-tions as 

 when giv(Mi to these animals by mouth, tlnis ai)])ai'eii1ly (>xcluding the 

 bowel as a (M)iiti-il)iit('f to the d(M're;ised tolerance. It is unlikely also 

 lliat 1li(' ki(hieys in pliosplioi'izcd animals wei'c iHMulci'ed abnoniially 

 ))t'nneal)h' for galactose, since when the kidneys alone are ))liosi)liorized 

 without affeeting the liver, the excretion of galactose after adminis- 

 tration l)y mouth oi- into a xcin lias been retarded rather than ha.stened. 

 These princii)les ha\c iK'couie ineorjioi-ated in a clinical test for dis- 

 ease of the lie|»;itie | )a I'eneliv ma. When galactose is administered to a 



