Chinese Journal of Physiology

88 C. PAK anp B. E, READ

5. Hamsters.—Although intraperitoneal injection is liable to show irregular results on account of poor technique, it was the simplest procedure for this small animal. Table 7 is remarkable in that the comparative effects in this animal are opposite to those found in all the other animals used by us. In fig. 2 we givea picture of the comparative toxicity of the three isomers, as calculated from the average results

TABLE 7.

The M.L.D. of ephedrine, ephetonin and pseudoephedrine in hamsters by intraperitoneal injection

Ephedrine HCl Ephetonin HCl Pseudoephedrine HCl Dose per s kg of - Hamsters | Hamsters |) Hamsters | Hamsters || Hamsters | Hamsters body weight used died used died used died

200-270 12 3 12 2 6 1 280 3 0 6 2 0 0 290 (0) 0 3 0 0 0 300 6 (0) 15 7 6 2 310 9 3 9 7 9 7 320 9 2 9 6 9 6 330 9 3 6 6 9 7 340 6 0 3 2 3 3 350 6 4 3 2 3 3

360-400 12 12 0 0 6 6

September 1928. Temperature 20° to 27°C.

3 x 100 — 120 so — 110 80 =] 100 7o a 90 co >| re so +4 Jo ao 4 so H H mo f 30 ae 50 i =e i: E yo Si f=f=ic 20 yu <2 Ho Ors = fo — Bo G i PERS ES] 4 30 3. B ‘| 10 2 ( = Hy = me F o —. 20 . — Sa Fig. 2a. Comparative magnitudes Fig. 2b. Comparative magnitudes of average M. L. D. of ephedrine, of M. L. D. of ephedrine, ephetonin and ephetonin and pseudoephedrine from pseudoephedrine in hamster by intra-

various animals. ; peritoneal injection.