Abstract:

Objective: To identify the basic chemical compositions of panax ginseng glycoprotein,and to discuss its influence in the scopolamine-induced study and memory impairment in the mice. Methods: Hollow fiber ultrafiltration device was used to separate the ginseng aqueous extract which saponin had been removed.The content of total sugar was determined by phenol sulfuric acid method;the content of protein was determined by Lowry method;the purity and relative molecular weight distribution were determined by HPLC;the sugar compositions were analyzed after the preparation of PMP derivatives.The mouse model with acquired memory disorder was established through injection of scopolamine.A total of 60 mice were randomly divided into control group(normol mice),model group(intraperitoneal administration of scopolamine hydrobromide 2.5 mg·kg^-1 after training),positive drug group(intragastric administration of piracetam 9 mg·kg^-1 for 30 d before training),and low,middle and high doses of Panax ginseng glycoprotein groups (intragastric administration of glycoprotein 7.5,75.0,225.0 mg·kg^-1 respectively for 30 d before training),and there were 10 rats in each group.The escape latency and the number of crossing the platform of the mice were determined by Morris water maze and step-down test. Results: The total sugar mass fraction of Panax ginseng glycoprotein was 58.41% which was consisted of 7 kinds of sugars.The mass fraction of protein was 19.93% which was consisted of 17 kinds of amino acids.The relative molecular weights of Panax ginseng glycoprotein were 200-50 000.The Morris water maze test results showed that from the 3rd day,the average escape latency of mice in high dose of Panax ginseng glycoprotein group was significantly shortened compared with model group (P<0.05),and the number of crossing the platform in high dose of Panax ginseng glycoprotein group was significantly more than that in model group (P<0.01).The relative position test results showed that the time of spenting in the platform quadrant s of the mice within 60 s in high dose of Panax ginseng glycoprotein group was significantly prolonged compared with model group (P<0.05);from the 2 day,the average escape latency in different doses of Panax ginseng glycoprotein groups was significantly shortened compared with model group (P<0.05).The step-down test results showed that the mice in different doses of Panax ginseng glycoprotein groups made significantly less mistakes within 3 min compared with model group(P<0.05);compared with model group,the latent period of landing on the platform of the mice in middle dose of Panax ginseng glycoprotein group was significantly increased(P<0.05). Conclusion: Panax ginseng glycoprotein could improve the memory ability of mice.

Key words: Panax ginseng, glycoprotein, study ability, memory ability, scopolamine