Cardiotonic constituent

From A. membranaceous, Wang [145] obtained a saponin-enriched extract and studied its effect on the isolated heart of rats. At doses of more than 50 ftg/ml, the extract showed a positive inotropic effect, which turned negative at 30 p.g/ml. The mechanism was similar to that of cardiotonic glycosides. By bioactivity-guided fractionation, the active constituent with positive inotropic activity was isolated and characterized as astragaloside IV [146]. 

Maytenus scutioides (Lourteig and O Donnell) is a subtropical shrub that is distributed in the Chaco (North of Argentina and South of Paraguay and Bolivia). The aerial part of this plant has been used as cardiotonic and the roots as abortive by the inhabitants of these regions. Recently, in their research for new bioactive compounds, Gonzalez et al [252] investigated the root bark of M. scutioides for cytostatic and antibiotic constituents. Thus, by bioactivity-directed fractionation, scutione (191), a new... 

R(+)-demethylcoclaurine, which possesses the same plane chemical structure as that of higenamine, was isolated as a smooth muscle and uterine relaxant constituent [8]. According to Kosuge and Yokota [6], it is known that catecholamines with this type of structure also show adrenaline P-type stimulant activity, and that the activity is stronger in the S series than in the R series. The strong cardiotonic activity of higenamine isolated from the roots of Aconitum sp. is explained by the fact that this alkaloid is in the racemic d/-form, and thus half of it is S(-)-demethylcoclaurine. 

Ayurveda has described Ocimum sanctum to have insecticide and pest repellent activities, and for this reason it is grown in most gardens. It is particularly said to act as a repellent against anopheles mosquitoes. The leaves are the most commonly used part and are applied locally on wounds. Topical application is believed to improve blood circulation. It has been prescribed for ear-ache. The juice of the leaves is also described as having digestive, laxative and antihelminthic properties. Apart from having a cardiotonic activity, its actions on the respiratory tract have made it a popular constituent of most therapies for respiratory infections. It also has antipyretic effects and has been prescribed for skin conditions such as leprosy [36]. 

Compounds associated with cardiotonic activity include hyperoside, vitexin, vitexin-2 -rhamnoside, oligomeric procyanidins, and (—)-epicatechin. Tbe flavonoids and oligomeric procyanidins have a tonic effect on tbe cardiac muscles, are negatively cbronotropic and dromotropic, and also show tbe bradycar-diac effect commonly noted for Crataegus (list and horhammer)/ Flavonoids may also be the major constituents responsible for the hypolipidemic effect of hawthorn by regulating lipoprotein lipases expression. ... 

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