MILTON AND SABINE WENDLANDT

328
A. S. MILTON AND S. WENDLANDT
RESULTS
Cats
PGE1. As shown in Table 1, the injection, at room temperature (20-
220 C), of PGE1 in doses between 10 ng and 10 ,sg produced a dose dependent
rise in temperature. Temperature began to rise after a latent period
which was independent of the dose and varied between 30 sec and 3 min
(mean of twelve experiments 1 min). On the other hand, the time at which
the maximum rise was attained and the duration of the rise were dose
dependent as shown in columns 6 and 7 of Table 1. The threshold dose
&
+2
E +1
U
C
C
lOng 100 ng 1 0 Ig
0 1 2 3 4 5 0 1 2 3 4 5
Hours Hours
(day 1) (day 5)
Fig. 1. Rectal temperature of the unanaesthetized cat. At the arrows
injections into the third ventricle of PGE1 in the doses as indicated. The
first two injections were made on the same day, the third injection 5 days
later.
was about 10 ng (2-8 x 10-11 M). Fig. 1 illustrates the effect of this dose and
of two larger ones on the same cat. The rise produced by 10 ng was
0. 30 C, by 100 ng 1.10 C and by 1 fig, given 5 days later, 20 C.
The rises were associated with skin vasoconstriction as evidenced by the
coldness of the ears, nose and paws, and by shivering. It was vigorous and
widespread after the larger doses of PGE1. As the temperature reached its
maximum, shivering decreased and finally ceased. With doses of 1 and
10ong piloerection occurred regularly during the vigorous shivering; with
smaller doses piloerection was not regularly observed. After 1 and 10 FuZg
the vigorously shivering cat was usually sitting quietly in the cage with
the head lowered, the eyes closed and the forepaws tucked under the body.
In this condition, some cats responded to touch and external stimuli,