The aim of this study was to find out whether the mouse in acute normobaric
hypoxia (3.5% O2) may be appropriate as a screening model for testing cerebroprotective drugs. The survival time of the mice in
hypoxia was used to determine
drug effects. 39 agents with various pharmacological and toxicological properties were investigated. Cerebroprotective, centrally depressant and stimulating as well as
cardiovascular drugs were included. Only 6 out of 16 cerebroprotective drugs used therapeutically prolonged the survival time of mice in acute
hypoxia. However, a positive effect was demonstrable especially for those cerebroprotective drugs (extractum Ginkgo bilobae,
meclofenoxate,
naftidrofuryl,
pentoxifylline and
pyritinol), which are generally accepted to be active. On the other hand, 12 out of 23 drugs which are therapeutically used as
cardiovascular drugs,
central stimulants or depressants or have known toxicological effects also prolonged the survival time of mice in
hypoxia. Thus, it became clear that the result of this
hypoxia test may be influenced by various pharmacological actions. Especially drugs stimulating the cardiovascular system or depressing CNS activity could prolong the survival time of mice in
hypoxia, whereas drugs with vasodilating effects could even shorten it. Opposite effects could superpose or neutralize each other. Therefore, the mouse in acute
hypoxia seems to be of limited value as a screening model for testing cerebroprotective drugs.