a 
216 Thyroid and Acidosis 
acidosis is used to express an actual increase in the hydrogen ion concen- 
tration of the blood as well as a lowering of the alkali reserve. It has 
been pointed out that free carbon dioxide is present in the body fluids in 
such concentration that it automatically converts into bicarbonates all 
bases not bound by other acids. In acidosis the concentration of bicar- 
bonate in the blood is always reduced below the normal level. As a sensi- 
tive indicator of this condition and its severity, the carbon dioxide capacity 
of the plasma was determined by Van Slyke and Cullen.® 
Since thyroid feeding can decrease the glycogen content of the 
liver very easily, possibly acidosis plays some réle here. 
Methods. 
Full grown rabbits were used. 3 gm. of desiccated’ thyroid, 
suspended in water, were given by a stomach sound every 
afternoon. Oats or greens (cabbage and carrot tops) were 
given as food. As shown by Sherman and Gettler,® and Mc- 
Danell and Underhill,’ the kind of food has a marked influence 
upon the acid-base equilibrium of the organism. Attention to 
this was, therefore, paid both in the preparatory and the thyroid 
period. When greens were given, the thyroid-fed rabbits con- 
tinued to take them until the later part of the thyroid period m 
about the same quantities as in the preparatory period. In the 
case of the oat diet, the appetite of the animal was greatly af- 
fected by thyroid feeding. They stopped eating this food in a 
few days. As control experiments, therefore, rabbits were fasted 
and others were fed on desiccated animal tissue other than thy- 
roid, no other food being added. As such a tissue powder, a 
mixture of desiccated spleen, kidney, and parotid gland in equal 
proportions was used. The amount and the method of adminis- 
tration of this powder were the same as in thyroid feeding. 
The urine was examined for protein and casts from time to time. 
The hydrogen ion concentration of the blood was determined 
by Marriott’s method.? 1 cc. of oxalated venous blood was 
used for dialysis. After comparing the color, produced by phe- 
nolsulfonephthalein, with the standard colors, the dialysate was 
’ Van Slyke, D. D., and Cullen, G. E., J. Biol. Chem., 1917, xxx, 289. 
6 Sherman, H. C., and Gettler, A. O., J. Biol. Chem., 1912, xi, 323. 
7 MecDanell, L., and Underhill, F. P., J. Biol. Chem., 1917, xxix, 233. 
8 Marriott, W. McK., Arch. Int. Med., 1916, xvii, 840. 
