832 
It is well known that some people are less sensitive to the 
poisoning action of cocain than others. According to HarcHer and 
EGGLEsTON *) cases are known in which 16 mgr. and 20 mgr. given 
subcutaneously were fatal, whereas in other cases 1.25 grms of 
cocain given subcutaneously had no effect whatever. HATCHER and 
EGGLESTON have proved conclusively that cocain, novocain and many 
other local anaesthetics become inactive very soon after being in- 
jected into an animal, while they have also demonstrated that 
various tissues, above all the liver, are able to decompose these 
poisons chemically. This, indeed was no novel experience, for 
Bier already found, when experimenting with rabbits, that cocain 
that has for some time been in contact with animal tissue, has 
thereby become less active, while Sano*) had come to the same 
conclusion for cocain with respect to brain-substance. Bier and Sano 
believed that this inactivation was caused by chemical decomposition. 
HATCHER aud Heeieston’s assertion that the liver can decompose 
cocain to a large extent, is incontestible. Still, this decomposing 
process cannot be so quick as to afford an explanation for the large 
differences in the sensitivity of different people. When after an in- 
jection of a few milligrammes of cocain the patient shows after a 
short time (a few minutes) serious symptoms of intoxication, the 
reason can not be that the cocain in his body is not decomposed 
quickly enough, for this decomposition cannot be so quick even 
with normal individuals. This, in fact, has also been pointed out by 
HATCHER and Keerrston themselves. Now it would seem to us that 
the abnormal sensitivity of some individuals to cocain might be ex- 
plained as follows: When cocain is administered to a normal man 
or animal it will be used: 
A in those places (i.a. the central and peripheral nervous system) 
where it exerts an influence. 
B in other places (i.a. free chemoreceptors distributed in the blood). 
The sensitivity of a special individual to cocain will then be largeiy 
determined by the ratio between the number of the places of adsorp- 
tion referred to under A and B. *) 
1) C. Eeereston and R. Harcuer. A further contribution to the pharmacology 
of the local anaesthetics. Journ. Pharm. and exp. Therap. vol. XIII. p. 433. 1919. 
2) Torata Sano. Ueber die Entgiftung von Strychnin und Kokain durch das 
Riickenmark. Ein Beitrag zur physiologischen Differenzierung der einzelnen 
Rückenmarks-abschnitte. Pfliigers Arch. Bd. 120; p. 367. 1907. 
Torata Sano. Ueber das entgiftende Vermögen einzelner Gehirnabschnitte gegen- 
über dem Strychnin. Pflügers. Arch. Bd. 124, p. 369. 1908. 
3) The places of adsorption sub A may be termed “dominant chemoreceptors”, 
those sub B “secondary chemoreceptors.” 
