title: Olfactory stimulation with scent of grapefruit oil affects autonomic nerves, lipolysis and appetite in rats.
abstract: In a previous study, we found that olfactory stimulation with scent of grapefruit oil (SGFO) excites the sympathetic nerve innervating the white adipose tissue in rats. Here we further examined the effects of SGFO in rats and observed that olfactory stimulation with SGFO excited the sympathetic nerves innervating the brown adipose tissue and adrenal gland and inhibited the parasympathetic gastric nerve. Local anesthesia of the nasal mucosa with xylocaine or anosmic treatment using ZnSO4 eliminated the autonomic changes caused by SGFO. Moreover, stimulation with SGFO elevated the plasma glycerol level, and treatment with either ZnSO4 or an intraperitoneal injection of diphenhydramine, a histamine H1 receptor-antagonist, abolished the glycerol elevation by SGFO. Furthermore, a 15-min exposure to SGFO three times a week reduced food intake and body weight. Finally, limonene, a component of grapefruit oil, induced responses similar to those caused by SGFO, and diphenhydramine eliminated the glycerol response to limonene. Thus, the scent of grapefruit oil, and particularly its primary component limonene, affects autonomic nerves, enhances lipolysis through a histaminergic response, and reduces appetite and body weight.
authors.affiliation: Division of Protein Metabolism, Institute for Protein Research, Osaka University, 3-2 Yamada-Oka, Suita, Osaka 565-0871, Japan.
authors.forename: Jiao
authors.initials: J
authors.lastname: Shen
authors.forename: Akira
authors.initials: A
authors.lastname: Niijima
authors.forename: Mamoru
authors.initials: M
authors.lastname: Tanida
authors.forename: Yuko
authors.initials: Y
authors.lastname: Horii
authors.forename: Keiko
authors.initials: K
authors.lastname: Maeda
authors.forename: Katsuya
authors.initials: K
authors.lastname: Nagai
mesh_terms: D000273:Adipose Tissue / Q000294:innervation / Q000502:physiology; D000311:Adrenal Glands / Q000294:innervation / Q000502:physiology; D000818:Animals; D001066:Appetite / Q000187:drug effects* / Q000502:physiology; D001835:Body Weight / Q000187:drug effects / Q000502:physiology; D032083:Citrus paradisi / Q000737:chemistry; D053138:Cyclohexenes; D005990:Glycerol / Q000097:blood; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D000077222:Limonene; D008066:Lipolysis / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009297:Nasal Mucosa / Q000187:drug effects / Q000502:physiology / Q000503:physiopathology; D009833:Olfactory Pathways / Q000187:drug effects* / Q000502:physiology; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013270:Stomach / Q000294:innervation / Q000502:physiology; D017779:Sympathetic Fibers, Postganglionic / Q000187:drug effects / Q000502:physiology; D013564:Sympathetic Nervous System / Q000187:drug effects* / Q000502:physiology; D013729:Terpenes / Q000494:pharmacology; D014630:Vagus Nerve / Q000187:drug effects* / Q000502:physiology; D019287:Zinc Sulfate / Q000494:pharmacology
chemical_list: D053138:Cyclohexenes; D006634:Histamine H1 Antagonists; D010936:Plant Extracts; D013729:Terpenes; D019287:Zinc Sulfate; D000077222:Limonene; D005990:Glycerol