Effects of nicotine on regional blood flow in the olfactory bulb in rats

Effects of nicotine on blood flow in the olfactory bulb were examined in anesthetized rats. Nicotine administered intravenously at 100 μg/kg increased regional blood flow in the olfactory bulb, irrespective of changes in systemic arterial pressure. Nicotine administered locally into the internal carotid artery at 10 μg increased blood flow, without changing arterial pressure; this response was abolished by hexamethonium. These results indicate that nicotine produces vasodilatation in the olfactory bulb via activation of nicotinic receptors located close to the olfactory bulb. Nicotine may be of therapeutic value in improving blood flow in the olfactory bulb.