Hypoglycemic effect of Equisetum myriochaetum aerial parts on streptozotocin diabetic rats

The hypoglycemic effect of water as well as butanolic extracts prepared from aerial parts of Equisetum myriochaetum (Equisetaceae) was examined in streptozotocin induced diabetic rats. A single oral administration of the water extract (WE) at doses of 7 and 13 mg/kg and of the butanol extract (BE) at doses of 8 and 16 mg/kg significantly (P<0.001) lowered the plasma glucose levels in diabetic rats after three hours of the administration. As a reference drug glibenclamide was used and showed, at a dose of 3 mg/kg, similar hypoglycemic effect like the tested extracts. Three kaempferol glucosides and one caffeoyl glucoside were isolated from the drug and were shown to be the main constituents in both extracts.