256 Studies in Metabolism. I 
we used six rabbits and carefully observed the symptoms after 
the injection of various quantities of guanidine. The following 
table shows that 0.2 gm. per kilo of body weight is suitable for 
this purpose. As a rule all the rabbits which were used in the 
present work had neither food nor water for 24 hours after the 
injection. Immediately after the injection the rabbits usually 
‘TABLE L. 
Symptoms after Injecting Various Doses of Guanidine Hydrochloride. 
~ Guan- 
coe 7 idine Time of 
4 = Date. Weight. hee injestiou: Symptoms and remarks. 
fa kilo. 
1917 gm. qm. 
1 | June 26 | 2,606} 0.10} 2.07 p.m. | No symptoms, recovered. 
Z 201 2004 ORL oO eueei aa 3.30 p.m. Dyspnea, twitching of 
head, jerking of head _ back- 
wards and forwards, tremor in 
extremities, lying down with 
hind legs stretched. Symptoms 
disappeared by 5 p.m. Recoy- 
ered. 
3 CON 284027008 1.0220), 2 eo mece No symptoms except slight dys- 
pnea. Recovered. 
4 “28 | 2,500 | 0.25} 10.50 a.m. | 11.30 a.m. Lying down with hind 
legs stretched, dyspnea, chat- 
tering of teeth, jerking of head. 
Symptoms disappeared by 1 
p-m. Died. 
5 “28 | 2,800 | 0.30) 10.55 “- | Quiet. No other symptoms. 
Died. 
6 “<- 29 | 2,600 | 0.40) 11 = 12.30 p.m. Lying down with hind 
legs stretched, sometimes 
twitching of extremities, es- 
pecially hind legs. Paralysis 
appeared later in legs. Con- 
vulsions. Died. 
run about because of the irritation produced by the injected 
drug. They remain quiet thereafter until the typical tetany 
symptoms appear—usually 1 to 14 hours after the injection. In 
some cases in which small doses were administered the animal 
remained quiet and depressed; in other cases the animal became 
restless and showed slight dyspnea. When large doses were 
