HYPOTENSIVE ACTION OF SYRINGIN FROM SYRINGA-VULGARIS

Naturally occurring syringin was isolated from the bark of Syringa vul garis (Oleaceae), and its pharmacological action examined on anaesthet ized Wistar rats. When the drug was introduced intravenously, it cause d a dose dependent fall in systolic, diastolic and mean arterial blood pressure, whereas heart rate also decreased at a slightly higher dose . The hypotensive activity was not inhibited by antihistamine or antim uscarinic agents. Syringin has no effect on the presser effect induced by norepinephrine or carotid occlusion.