1972 Volume 92 Issue 2 Pages 135-140
Pharmacological studies were carried out on central effect of Chinese cinnamon which is one of the most important crude drugs in Chinese medicine. Chinese medicirie uses this crude drug as a sedative, antipyretic, and analgesic. Representative prescriptions which contain cinnamon are Keishikanzo-To ( ?? ?? ?? ?? ?? ), Keishikakei-To ( ?? ?? ?? ?? ?? ), and Ryokeijutsukan-To ( ?? ?? ?? ?? ?? ). Cinnamaldehyde and essential oil-free aqueous extract of Chinese cinnamon were examined using mice, and the following results were obtained. Cinnamaldehyde showed sedative activities (decrease of spontaneous motor activity, antagonistic effect to methamphetamine-induced hyperactivity, motor incoordination in rotar-rod test, and prolongation of hexobarbital-induced anesthesia) and hypothermic activity, as well as antipyretic one in typhoid-paratyphoid vaccine-febrile mice. After its administration, electrocorticogram in rabbits with chronically implanted electrodes indicated its shift to a low voltage and high frequency in the spontaneous discharge and a little prolongation of arousal response by acoustic stimulation. On the other hand, the aqueous extract did not show any remarkable activities, but this fact does not necessarily imply that the extract does not contain any pbarmacologically active substances. No synergistic effect of the two materials was obtained in two tests of ana1gesic effect in writhing symptom and inhibitory effect on methamphetamine-induced hyperactivity. Thus, cinnamaldehyde was found to play some part in the therapeutic effect of cinnamon.