Aim To find the material foundation of treatment for diabetes in Coptidis Rhizoma ( RC ) . Methods The antihyperglycemic effect of RC alka-loids ( berberine, coptisine, palmatine, epiberberine, and jatrorrhizine) was evaluated in spontaneity diabe-tes KK-Ay mice. Results After 40 days′ oral admin-istration ( 225 mg · kg-1 · d-1 , ig ) , berberine and coptisine significantly suppressed the elevated fasting blood glucose level and ameliorated the glucose toler-ance . Body weight gain of KK-Ay mice was significant-ly decreased in the epiberberine-treated group. Berber-ine improved insulin resistance and jatrorrhizine in-creased the SOD activity, decreased the MDA level. Conclusions These results indicate that the main an-tihypoglycemic effect constituents are berberine and coptisine, while they show different mechanisms. Pal-matine, epiberberine and jatrorrhizine display different potential roles in the treatment of diabetes. The meth-ylene-dioxy groups at the C-2 , C-3 , C-9 and C-10 po-sitions are indispensable for antihyperglycemic effect of RC alkaloids.

Aim To study the hypnotic effect of five alkaloids extracted from Rhizoma Coptidis (berberine , coptisine,palmatine,epiberberine,jatrorrhizine )in mice,and preliminarily explore its underlying mecha-nism.Methods The experiments of locomotor activity and hypnosis induced by suprathreshold and subthresh-old doses of pentobarbital sodium were used to evaluate the effect of drugs on sleep behavior in mice.Then, HPLC-FLD was used to detect the contents of NE,DA and 5-HT on PCPA mice model.Results Compared with control group,berberine and coptisine notably in-hibited spontaneous activity in behavioral experiments (P <0.05),and increased the sleeping percentage of mice under subthreshold dose of pentobarbital sodium. Berberine and coptisine shortened the period of sleep latency,and prolonged the sustained period of sleeping at suprathreshold dose in mice (P <0.05 or P <0.01 ).Other alkaloids had no significant differences in sleep latency and period of sleep observed in this current experiment.Compared with PCPA mice model group,berberine and coptisine remarkably increased the contents of NE and 5-HT (P <0.01 ),but they had no effects on DA.Conclusions Berberine and coptisine may play a sedative and hypnotic role in PC-PA mice by increasing contents of 5-HT and NE in hy-pothalamus,and the sedative and hypnotic effects of berberine are stronger than those of coptisine.Other alkaloids have no effects on sleeping in mice.