Studies of Epilobium angustifolium extracts on growth of accessory sexual organs in rats

Hexane and water extracts, as well as an ultrafiltration fraction (MW < 1000 Da) obtained from the water extract from Epilobium angustifolium L. (Onagraceae) were administered perorally (p.o.) on intact male rats as well as on testosterone stimulated castrated rats and changes in growth of prostate, musculus laevator ani and seminal vesicles were determined. In intact rats the water extract decreased the weight of seminal vesicles whereas in castrated rats an increased weight of all accessory sexual organs was observed. In intact rats the ultrafiltration fraction (MW < 1000 Da) exhibited the same but smaller effect than the water extract, in testosterone stimulated castrated rats it showed no effect in comparison with the control group. The hexane extract exhibited no significant effects, both in intact and testosterone stimulated castrated rats. For characterization the hexane extract was analyzed for the first time for its fatty acid composition by GC-MS.