Biol. Pharm. Bull. 29(9) 1868—1872 (2006)

ubiquitously in plants, have a variety of biological activities including anti-viral, anti-tumor, anti-inflammatory and vasodilatory actions. Because of these biological activities and their bioavailability in the brain in particular, they are supposed to have effects of neural protection. Nicotiflorin (kaempferol-3-b-rutinoside), a flavonoid glucoside originally derived from the flower petals of Flos Carthami, a medicinal plant traditionally used in prevention and treatment of cardiovascular diseases and thrombosis in Chinese medicine, is known to have potent analgesic, antihypertensive and antianaphylactic effects. In an analgesic model of writhing syndrome in mouse, nicotiflorin was to significantly reduce the number of writhings and stretchings induced by 1% acetic acid solution at a dose of 80 and 40 mg/kg. In normotensive pentothal anaesthetized rats, intravenous administration of nicotiflorin produced a dose dependent decrease in systolic, diastolic and mean arterial blood pressure. At a dose of 10 mg/kg the antihypertensive effect (41.60% 3.62) was observed with a duration of 2—3 min, during which the heart rate also decreased. These effects are not mediated through muscarinic, histaminergic and adeno ceptors. In antianaphylactic studies, it can significantly prevent fatal shock of hen egg-white lysozyme specific IgE-mediated anaphylaxis. However, little information is available about the effects of nicotiflorin on the CNS. To determine whether it has neuroprotective effects in vivo, this study observed its effects on ischemic brain damage using a permanent model of focal ischemia in rats. Furthermore, in order to define the possible protective mechanism, we examined the effect of it on cell damage induced by an acute hypoxic insult in rat primarily cultured neurons.