title: Hypoglycaemic activity of dioscoretine from tubers of Dioscorea dumetorum in normal and alloxan diabetic rabbits.
abstract: Dioscoretine isolated from the aqueous fraction of the methanol extract of Dioscorea dumetorum tubers when administered intra-peritoneally to normal and alloxan diabetic rabbits produces significant hypoglycaemic effects at a dose of 20 mg/kg. The fasting blood sugar in normoglycaemic rabbits was reduced from 112 mg/100 ml to 55 mg/100 ml after 4 hours. In alloxan diabetic rabbits, the blood sugar was lowered from 520 mg/100 ml to 286 mg/100 ml at the same time interval. The aqueous fraction of the methanol extract produced comparable effects at 100 mg/kg. The chloroform fraction of the same extract raised the fasting blood sugar of normal rabbits to 196 mg/100 ml after 6 h. The acute toxicity studies gave LD50 values of 1.4 g/kg for the aqueous fraction and 0.58 g/kg for dioscoretine when tested on mice. The hypoglycaemic effects were compared to those of tolbutamide.
authors.affiliation: Phytotherapy Research Laboratory, Faculty of Pharmaceutical Sciences, University of Nigeria, Nsukka.
authors.forename: M M
authors.initials: MM
authors.lastname: Iwu
authors.forename: C O
authors.initials: CO
authors.lastname: Okunji
authors.forename: G O
authors.initials: GO
authors.lastname: Ohiaeri
authors.forename: P
authors.initials: P
authors.lastname: Akah
authors.forename: D
authors.initials: D
authors.lastname: Corley
authors.forename: M S
authors.initials: MS
authors.lastname: Tempesta
mesh_terms: D000470:Alkaloids / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use / Q000633:toxicity; D000496:Alloxan; D000818:Animals; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy*; D007004:Hypoglycemic Agents / Q000302:isolation & purification / Q000627:therapeutic use*; D010946:Plants, Medicinal / Q000032:analysis; D011817:Rabbits
chemical_list: D000470:Alkaloids; D019086:Bridged Bicyclo Compounds, Heterocyclic; D007004:Hypoglycemic Agents; C064385:dioscoretine; D000496:Alloxan