Endothelium modulated vasorelaxant response of a polypharmaceutical herbal drug (lipotab) and its individual constituents

The present study was undertaken to examine the endothelium modulated effects of polypharmaceutical drug lipotab and its individual ingredients in isolated aortic rings of rat. Endothelium intact and denuded aortic rings were precontracted with phenylephrine 10(-6) M and drugs were added in cumulative manner in concentration ranging from 1 to 50 mu g/ml. The results demonstrated an endothelium-dependent vasorelaxant effect of lipotab and its individual ingredients. with the exception of nicotinic acid. The dose dependent relaxant response of nicotinic acid was not altered significantly in the endothelium-denuded rings, suggesting a direct effect of the drug on the vascular smooth muscle. Vasorelaxant effect of lipotab and its individual constituents suggests the therapeutic potential of these compounds in certain cardiovascular diseases. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.