CITRULLUS COLOCYNTHIS

Objectives: To evaluate the methanolic extract of Citrullus colocynthis andits different fractions for possible spasmogenic effects on rat’s ileum model. Study Design:An experimental study. Setting: Department of Pharmacology, Institute of Basic MedicalSciences, Khyber Medical University, Hayatabad, Peshawar. Period: August 2016 to March2017. Methodology: Different fractions i.e n-hexane, chloroform, Ethyl acetate, n-butanol andaqueous fractions of methanolic extract were tried in concentrations of 0.01, 0.03, 0.1, 0.3, 1.0,3.0, 5.0, 10 and 15 mg/ml to identify the portion with maximum spasmogens. Results: Aqueousand n-Butanol fractions showed spasmogenic effects on the spontaneous contractions of rat’sileal preparations at the concentrations of 0.1, 0.3, 1.0, 3.0 and 5.0 mg/ml while at 10 and15 mg/ml, they showed spasmolytic effects. Ethyl acetate and chloroform fractions did notshow significant spasmogenic effects, rather showed spasmolytic effects in rabbit’s jejunalpreparations with respective EC50 values of 0.1283 ± 0.007 mg/ml and 2.703 ± 0.235 mg/ml. Respective EC50 values for spasmolytic effects of Ethyl acetate and chloroform fractionsupon KCl induced contractions were 5.37 ± 0.515 mg/ml and 12.36 ± 1.484 mg/ml. RespectiveEC50 (log [Ca++] M) of ethyl acetate fraction at 1mg/ml vs control were -2.563 ± 0.04 and-2.846 ± 0.035. Similarly, respective EC50 (Log[Ca++]M) in the absence and presence of0.1 μM verapamil were -2.45 ± 0.06 and -1.7 ± 0.07. EC50 (log [Ca++] M) for control vschloroform fraction at 3 mg/ml and 5 mg/ml were -2.95 ± 0.035 vs -3.02 ± 0.03 and -3.06 ±0.0264, respectively. Similarly, respective EC50 (Log[Ca++]M) in the absence and presenceof 0.1 μM verapamil were -2.45 ± 0.06 and -1.7 ± 0.07. Conclusion: Thus, it is concluded thatspasmogens concentrated in the residual aqueous fraction followed by n-butanol fraction whilespasmolytic constituents are concentrated in the ethyl acetate fraction followed by chloroformfraction.