938 
action, we are also entitled to expect that, if the adrenalin is to act 
upon an animal in which the serum is replaced by physiological 
salt-solution, the adrenalin will work less intensely. We have endeav- 
oured to test this supposition experimentally. 
For this purpose we performed in cats so-called plasmaphaeresis 
after Agur 5). These animals were bled and were given an injection 
of RinGer’s solution to replace the deprived blood, first pare RiNGeR’s 
solution and afterwards RiNGer’s solution to which had been added 
red bloodeells of the cat obtained from other cats. Before starting 
the plasmaphaeresis we have of course determined the sensitivity 
of the animal to adrenalin. 
The experiments were conducted as follows: 
Exp. 1. Cat 2,6 kg.; vagi severed; ether-narcosis. After injection of 0,005 mgr. 
of adrenalin fall of the bloodpressure from 76 to 54 mm. Hg., at another time 
from 92 to 76 mm. Hg. (Fig. 5@ and 0b). The animal is now bled from the 
carolis as much as possible and simultaneously warm Ringer’s solution (to which 
afterwards red blood-cells are added) is injected into the vena femoralis. By this 
we manage to keep the bloodpressure up to the mark (96 mm. Hg.). Injection of 
0,005 mgr. of adrenalin has now no effect at all (5c) 0,01 mgr. yields a 
slight rise. 
Exp. 2. Gat 1,27 kg.: ether-narcosis. Injection of 0,005 mgr. of adrenalin 
causes a rise of the bloodpressure from 110 to 114 mm. Hg. The animal is bled 
and given Tyrode-solution —+ red bloodcells. The bloodpressure is lowered; 
0,005 mgr. of adrenalin still produces a rise from 34 to 44; addition of a small 
dosis of cat's serum or peptone to the adrenalin-solution does not intensify the _ 
action. The blooding had not been sufficient in this case. 
Exp. 8. Cat. Vagi cut; ether-narcosis. Injection of 0,005 mgr. of adrenalin yields 
a rise of the bloodpressure from 168 to 178 mm. Hg. (Fig. 6a). Injection of 
adrenalin + 1/, ¢.c. serum from another cat has the same effect. After blooding 
and injection of Tyrode solution + red bloodeells the bloodpressure falls to 78. 
Injection of 0,005 mgr. and of C,Ol mgr. of adrenalin no longer affects the 
bloodpressure (Fig. 6b). After injection of a fresh quantity of bloodcells the blood- 
pressure rises up to 110 mm. Hg. Injection of 0,01 mgr. of adrenalin has no 
action, little by little the bloodpressure decreases spontaneously; when il has 
reached 62 mm. Hg., again 0,01 mgr. of adrenalin is given. This is almost quite 
imeffectual. (Fig. 6c). By an injection of red bloodcells the bloodpressure is raised 
to 150 mm. Hg., 0,01 mgr. is inactive (Fig. 6d). An injection of 0,005 mgr. of 
adrenalin + !/, c.c. serum from the same cat has no influence. The bloodpressure 
has meanwhile decreased to 78 mm. Hg, 0,01 mgr. of adrenalin has no effect. 
(Fig. 6e). By an injection of 10 cc serum from another cat the bloodpressure is 
increased again to JOO mm. Hg., now 0,01 mgr. of adrenalin gives a distinct 
rise of the bloodpressure (Wig. 6f). After another injection of 8 e.c of cat’s serum 
0,01 mgr. of adrenalin still causes a distinct though insignificant rise. 
Exp. 4. Cat 3 kg. Vagi cut; ether-narcosis. 0,005 mgr. of adrenalin causes 
1) J. Apen, L. Rowntree and B. Turner. Plasma removal with return of cor- 
puscles. (Plasmaphaeresis) Journal of Pharm. and exp. Ther. Vol. 5 p. 625 1914. 
