| In vitro: | 
				| Bioorganic & Medicinal Chemistry Letters,2002,12(3): 477–482.  |  | Protective effects of polygodial and related compounds on ethanol-induced gastric mucosal lesions in rats: structural requirements and mode of action[Reference: WebLink] |  The methanolic extract from the leaves of Tasmannia lanceolata was found to potently inhibit ethanol-induced gastric lesions in rats. 
 METHODS AND RESULTS: 
Through bioassay-guided separation, three known sesquiterpenes, polygodial, polygodial 12α-acetal, and polygodial 12β-acetal, and a new sesquiterpene, Methyl isodrimeninol, were isolated as the active constituents. Among them, polygodial showed very potent gastroprotective effects (ED50=0.028 mg/kg, po). From the gastroprotective effects of various reduction and oxidation derivatives of polygodial, the dialdehyde or diacetal structure was found to be essential for the strong activity. 
 CONCLUSIONS: 
Since the gastroprotection of polygodial was attenuated by pretreatment with indomethacin, N-ethylmaleimide, NG-nitro-l-arginine methyl ester and ruthenium red, endogenous prostaglandins, sulfhydryl compounds, nitric oxide and vanilloid receptors may be involved in the protective activity. |  
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