Sedative Effects of Hot Flower Infusion of Nyctanthes arbo-tristis on Rats

Abstract

Hot infusion of Nyctanthes arho-lristis Linn. (Oleaceae) llowers are used often by some elderly Sri Lankan Buddhist monks as a potential sedative. However, in Ayurvedic, traditional and folkloric medicine of Sri Lanka, no Mich implication has been made regarding therapeutic activity of these flowers. The aim of this study was to investigate the sedative potential of N- arbo-lrislis flowers in rats using the hole-board technique. A hot flower infusion was made as used by the monks in different concentrations (3.7, 7.5. 12.5, or 18.7mg/kg) and was orally .idministered. Sedative potential was assessed 2h postucatment. The infusion had a moderate dose-dependent conscious sedative activity in male but, surprisingly, not m female rats. The infusion was well tolerated (in terms of overt toxic signs, liver or kidney functions) even following subchronic treatments and also did not show ,tny overt signs of dependence (classical signs of withdrawal reactions). Sedation appears to result mainly by antioxidant, membrane stabilizing, and by yet undiscovered mechanisms of sedative actions of anthocyanin, a tlavonoid, in the flower.