抄録
Recently, we observed that olfactory stimulation with scent of grapefruit essential oil caused excitations of sympathetic nerves innervating the epididymal (white) adipose tissure, interscapular (brown) adipose tissue and adrenal gland and inhibition of a parasympathetic nerve innervating the stomach. In contrast, olfactory stimulation with scent of lavender essential oil inhibited sympathetic nerves innervating the epididymal adipose tissue, interscapular adipose tissue and adrenal gland and excitated a parasympathetic nerve innervating the stomach. These findings suggest that the scent stimulation with grapefruit oil elevates lipolysis, thermogenesis, adrenaline secretion, thus, the blood glucose and the blood pressure, and suppression of food intake, and that the scent stimulation with lavender oil induced opposite responses. In the experiments examined this, we found evidences suggesting that these are the cases. Moreover, we observed that bilateral electrolytic lesions of the hypothalamic suprachiasmatic nucleus (SCN), a master circadian clock, and histaminergic blockers eliminated these responses. That is, a histamine H3-antagonist, thioperamide, abolished the effects of lavender oil and a histamine H1-receptor-antagonist, diphenhydramine, suppressed the effects of grapefruit oil. Anosmic treatment with zinc sulfate eliminated all of the changes due to olfactory stimulations. These findings suggest that olfactory stimulations with scents of grapefruit and lavender oils affect appetite and metabolism via the functions of the SCN and histaminergic nerve. [J Physiol Sci. 2006;56 Suppl:S55]
