Studies of Drug Action on the Behavior of Small Animals. I. : Central Nervous System Stimulants and their Combined Effects

Abstract

Two types of a behavior-recording apparatus were designed and prepared for small animals, such as the mouse. One is a triangular cage hung by spiral springs at three corners, The location of an animal at one corner is indicated by the corresponding electromagnetic lever on a kymograph paper as indicated in Fig. 1. The other one is also a triangular cage, in which a light beam is set at each corner and at the center of the cage. The interruption of a light beam is recorded on a rotating paper by the corresponding electromagnetic lever (Fig. 2) The effects of several central stimulants were tested with these apparatus. All the drugs were administered subcutaneously. Apparent difference in the behaviors was observed between Methamphetamine and other stimulants such as methylphenidate, pipradrol, and caffeine. methamphetamine increased the rotating movement of the animal more markedly than the other stimulants. Considerable rotating movements produced by 5mg./kg. of d-methamphetamine hydrochloride were disturbed by 1mg./kg. of LSD-25. The locomotive movement of the mouse was elevated by the administration of 5Omg./kg. of dimethylaminoethanol each day for 8 days and was further potentiated by 10mg./kg. of caffeine. The stimulating effect of 50 mg./kg. of dimethylaminoethanol was also potentiated by 1mg./kg. of LSD-25.