FUJIWARA Michihiro Faculty of Pharmaceutical Sciences, Fukuoka University, 薬学部, 助教授 (10091331)
NONAKA Gen-ichiro Faculty of Pharmaceutical Sciences, Kyushu University, 薬学部, 助教授 (60037611)
UEKI Showa Faculty of Pharmaceutical Sciences, Kyushu University, 薬学部, 教授 (80037564)
|Budget Amount *help
¥9,100,000 (Direct Cost: ¥9,100,000)
Fiscal Year 1987: ¥3,600,000 (Direct Cost: ¥3,600,000)
Fiscal Year 1986: ¥5,500,000 (Direct Cost: ¥5,500,000)
Chemical and pharmacological studies on RG-tannins which are principles of a rhubarb (GAO), exhibiting psychotropic activities, show them to be a new type of antipsychotic drugs having no behavioral toxicities such as an extraphramidal syndrome, etc, The followings are the summarized results of the work.
1. Chemical Studies
(1) RG-Tannins: An excellent procedure for the preparation of RG-tannins, as well as the methods for the chemical evaluation of their quality, has been newly developed, and also the possible chemical structures of RG-tannins have been established.
(2) Researches into the components of various rhubarbs:
Structural elucidation of phenolic components in a variety of commercial rhubarbs, as well as their chemical evaluation byh HPLC, has revealed that GAO is the most excellent material for manufacturing RG-tannins.
(3) Structural elucidation of proanthocyanidins:
As a result of chemical work on the structures of proanthocyanidins in various plant materials, some significant findings helpful for the structural elucidation of RG-tannins have been obtained.
2. Pharmacological Studies
(1) Behavioral pharmacological study:
On administration of RG-tannins, several pharmacological activities (inhibitory effect of exploratory behavior, anti-methanphetamine effect, taming effect (OB rat, THC rat), anti-noradrenaline effect, centrl anti-serotonin action and inhibition of conditioned avoidance responce) have been found, but anti-convulsion action, anti-conflict effect and inhibitory effect of muricide were not found.
(2) Neurochemical Research:
After administration of RG-tannins to OB rats, the levels of NA, Da and its metabolites, and 5-HT and its metabolites in each part of brain have been determined quantitatively, and it has become clear that RG-tannins block the receptors of NA,DA and 5-HT and also that this effect is regiospecific, especially the DA-receptor in striatum being not blocked.