CURARE ALKALOIDS. 
429 
§ 5I9-] 
of one of the frog’s legs before administering the poison, an insight into 
the true action of the drug is obtained. It is then found that the 
reflex excitability and power of motion in the leg are retained, although 
all the rest of the body is paralysed. The only explanation of this is 
that curare does not act centrally, but paralyses the intramuscular ends 
of the motor nerves. The experiments of Overend Hofman (“ Studien 
liber den Tetanus,” Pfinger's Archiv, Bd. xciii.), also show that curare 
has a special action on the muscular fibre itself, decreasing in a marked 
degree its power. Curare is eliminated partly through the liver and 
partly through the kidneys. Dragendorff found it in the faeces, while 
a striking proof that it is excreted by the kidneys is given by the 
experiment of Bidder, 1 in which the urine of a frog poisoned by curare 
was made to poison a second, and the urine of the second, a third. The 
easy excretion of curare through the kidneys furnishes an explanation 
of the relatively large dose of curare which can be taken by the stomach 
without injury. A dose which, given by subcutaneous injection, would 
produce violent symptoms, perhaps death, may yet be swallowed, and no 
ill effects follow. It is hence presumed that, in the first case, the poison 
is, comparatively speaking, slowly absorbed, and almost as fast separated, 
and put, as it were, outside the body by going into the urine ; while, in 
the other case, the whole dose is thrown suddenly into the circulation. 
§ 519. Separation of Curarine. —It is hardly probable that the 
toxicologist will have to look for curarine, unless it has entered the 
body by means of a wound or by subcutaneous injection ; so that in all 
cases the absorbed poison alone must be sought for. The seat of entry, 
the liver, the kidneys, and the urine are the only parts likely to be of 
any use. Dragendorff recommends the extraction of the tissues with 
water feebly acidulated with a mineral acid, to precipitate albuminous 
matters, etc., by strong alcohol, and the separation, by means of benzene, 
of fatty matters. The liquid is then made alkaline, and shaken up with 
petroleum ether, which removes certain alkaloidal matters. It is now 
evaporated to dryness, mixed with finely powdered glass, and extracted 
with absolute alcohol. The alcohol is evaporated to dryness, and any 
curarine extracted from this residue with water. By very careful 
drying up of this last extract, and taking it up in alcohol, the alkaloid 
is said to be obtained so pure as to respond to chemical tests. The 
identification may be by the colour reaction of sulphuric acid described 
ante, in all cases supplemented by its physiological action on frogs. 2 
1 Arch. f. Anat. u. Physiol., 1879, p. 598. 
2 It is known that curare may cause slight symptoms of excitation before the 
paralysis comes on. M. Couty has succeeded in isolating these symptoms by em¬ 
ploying feeble extracts of Strychnos triplinervia, or small doses of certain native pre¬ 
parations. By these means, in dogs, a new phase of intoxication may be present 
for ten or even twenty minutes. In the first instance the animal is agitated, jump¬ 
ing, scratching, barking, as if in a state of general hypersesthesia. Then it presents 
