S. Kuriyama 199 
latent diastase, which does not act in the physiological formation of 
sugar in the liver, while the liver of Rana fusca contains only a small 
amount of such latent diastase. In human diabetes, Wynhausen? failed 
to demonstrate any decided change of the blood diastase, while Myers 
and Killian’s recent studies?* showed a noteworthy increase. 
Feeding thyroid to cats, Burge, Kennedy, and Neill?” found that the 
catalase content of the blood increases markedly. On the other hand; 
Juschtschenko?® reported that thyroidectomy causes a decrease of the 
catalase content of the blood. Wells?® sought for a possible influence on 
autolysis of the liver by thyroid extract, but could demonstrate none in 
vitro. Schryver,®° however, found that autolysis was more rapid in the 
liver of dogs fed on thyroid extract for some days before death than it 
was in control animals. 
Concerning the influence of the thyroid upon the blood diastase, Wohl- 
gemuth!*® found a noteworthy decrease of the blood diastase in thyroidec- 
tomized goats. The diastase content of the blood serum of these animals 
was Dp: Shees-o 20, while the normal goat serum was valued at D- a = 
20 — 40. 
« 
I have made some experiments in order to ascertain whether 
the decrease of the glycogen content of the liver in hyperthy- 
roidism has any relation to the glycogenolytic action of the liver 
and blood serum. 
Records of these follow. 
Methods.—Rabbits were used for blood diastase determina- 
tion; rats for liver diastase. To the former, fresh pig thyroid 
was given; to the latter, desiccated thyroid. In rabbits, the 
blood was taken from an ear vein by puncture, and the serum 
separated. For determining the liver diastase, the organ was 
extirpated promptly after bleeding the animals and immersed in © 
warmed physiological saline solution. After weighing, the liver 
was freed from blood by perfusing with the same saline solution. 
The liver was then thoroughly ground in a mortar with four times 
its weight of physiological saline solution and a small amount 
of sand, placed in an ice box for 1 hour, and shaken from time to 
time. After filtration through a cloth, the homogeneous organ 
25 Wynhausen, O. J., Berl. klin. Woch., 1910, xlvii, 1281. 
26 Myers, V. C.,.and Killian, J. A., J. Biol. Chem., 1917, xxix, 179. 
27 Burge, W. E., Kennedy, J., and Neill, A. J., Am. J. Physiol., 1917, 
xliii, 433. 
28 Juschtschenko, A., Biochem. Z., 1910, xxv, 49. 
29 Wells, H: G., Am. J. Physiol., 1904, x1, 351. 
30 Schryver, S. B., J. Phystol., 1904-05, xxxii, 159. 
