The plant material was collected in the Tirunelveli district, Tamilnadu, India. It was authenticated by Dr.V.Chelladurai, Govt. Research officer, Botany C.C.R.A.S. Govt. of India, (Retired), Tirunelveli. A voucher specimen has been kept in our laboratory (As) for future reference

The root bark of Alangium salvifolium Sub.sp.Hexapetalum was dried under shade, coarsely powdered and passed through sieve no.22 to get particle of uniform size. Then extracted exhaustively with benzene and ethyl acetate using Soxhlet apparatus ⁴ . The solvent was removed under reduced pressure to obtain a solid mass. It was then preserved in a desiccators until further use.

Albino rats of both sex (150-250g) were collected and housed under standard laboratory conditions. They were fed with standard rat feed and water adlibitum. The experimental protocols were approved by institutional animal ethics committee (Approval no. 509/02/C/CPCSEA/2002).

The method of Lipschitz et al,[5] was employed for the evaluation of diuretic activity. The animals were divided in to four groups (six in each) deprived of food and water for 18h prior to the experiment. On the day of experiment, the Group I animals received normal saline (20 ml/kg. p.o.), the Group II animals received Frusemide (20 mg/kg. i.p.), the Group III and IV animals received benzene and ethyl acetate extracts (250 mg/kg) respectively. Immediately after the administration, the animals were kept in metallic cages (two per cage) specially designed to separate urine and feacal matter and kept at room temperature (20±0.5 ^o C). The total volume of urine was collected at the end of 24h. During this period no water and food was made available to the animals. The parameters accounted for ascertaining the diuretic activity are total volume of urine and the urine concentration of Na+, K+ and Cl-. The Na+ and K+ were measured by flame photometry[6] and Cl- concentration was estimated by titration[7] with silver nitrate solution (N/50) using 3 drops of potassium chromate as indicator.

The student ..t.. value was employed for statistical analysis. All the values expressed are Mean ± S.E.M. P< 0.05 (Compared to control) was considered significant.