440 
to induce a temporary inhibition of the intestinal movements, fall 
within the same limits. 
When combining these facts, the question arises whether perhaps 
the inhibition of small atropin-doses is to be considered as an antagonism 
for the cholin present in the intestinal wall. 
If this is the case, the inhibition of small quantities of atropin, 
will not appear when the cholin has been previously removed from 
the intestinal wall, but it will come forth again after the addition 
of cholin and subsequent administration of atropin. 
Aside from this inhibition of small quantities of atropin, its actual 
influence is, according to Magnus’s’) experiments, one that stimulates 
AurrBacus’s plexus. It is only large quantities that paralyse the nerve 
centra and muscles of the intestinal wall. ; 
The action of these latter quantities we leave out of consideration. 
Experimental evidence in support of the above hypothesis may be 
obtained in the following way : 
1st A gut, inhibited originally by small quantities of atropin, is 
to be brought into a condition in whieh a small quantity of atropin 
is without effect, through repeated washings, so that cholin is 
removed from the intestinal wall. 
2nd The atropin-effect is to reappear in this gut after giving cholin. 
ord. AG cuits which is originally inhibited by moderate quantities 
of atropin, is to be brought, through repeated washing, into a 
condition, in which the same quantity of atropin has only a stimu- 
appeared lating effect. 
The experiments made to prove this, were performed with the 
isolated small intestine of rabbits and guinea-pigs, which, as had 
before, are provided with rich quantities of cholin and — as may 
be expected, readily give them off to the environing fluid. 
Experiments with the small intestine of the rabbit. 
In the experiments with the small intestine of the rabbit a diffi- 
culty arose in that after some days the spontaneous movements 
diminished with the washing out of the cholin, which made the 
results less clear. 
Turning to account Laqurur’s?) experience that loops of intestine 
1) R. Maanus, Versuche am überlebenden Dünndarm von Säugetieren. V. Mitt, 
Pfliiger’s Archiv. Bd. 108, pag. 1, 1905. 
2) E. LAQveuR, Over den levensduur van geisoleerde zoogdier-organen met 
automatische functie. Verslagen Kon. Akademie v. Wetenschappen te Amsterdam. 
24 April 1914, XXII, p. 1818. 
