title: Expression of BDNF and TH mRNA in the brain following inhaled administration of α-pinene.
abstract: Essential oils are mainly administered by inhalation. Administration by inhalation is considered to occur through two pathways, neurological transfer and pharmacological transfer. However, the relationship between the two routes is not clear. To clarify this relationship, we administered α-pinene, which has an anxiolytic-like effect, to mice. Emotional behavior and accumulation and expression of relevant mRNAs in the brain (brain-derived neurotrophic factor (BDNF); tyrosine hydroxylase (TH)) were examined following inhaled administration of α-pinene (10 μL/L air for 60 or 90min). To evaluate the anxiolytic-like effect, the elevated plus maze (EPM) test was used. Inhalation of α-pinene for 60 min produced a significant increase in the total distance traveled in the EPM test compared with control (water). The concentration of α-pinene in the brain after 60 min of inhalation was significantly increased compared with that after 90 min of inhalation. The expression of BDNF mRNA in the olfactory bulb and in the hippocampus was almost the same after 60 min of inhalation compared to that after 90 min of inhalation. The expression of TH mRNA in the midbrain after 60 min of inhalation was significantly increased compared with that of the control. Thus, an increase in α-pinene in the brain induces an increase in TH mRNA expression and increases locomotor activity. The anxiolytic-like effect may be related to both neurological transfer and pharmacological transfer.
authors.affiliation: Faculty of Pharmaceutical Sciences, Toho University, Funabashi, Chiba, 274-8510, Japan.
authors.forename: Hikaru
authors.initials: H
authors.lastname: Kasuya
authors.forename: Narumi
authors.initials: N
authors.lastname: Okada
authors.forename: Mika
authors.initials: M
authors.lastname: Kubohara
authors.forename: Tadaaki
authors.initials: T
authors.lastname: Satou
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Masuo
authors.forename: Kazuo
authors.initials: K
authors.lastname: Koike
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology*; D001522:Behavior, Animal / Q000187:drug effects; D000081008:Bicyclic Monoterpenes; D001921:Brain / Q000187:drug effects; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D039821:Monoterpenes / Q000008:administration & dosage*; D009822:Oils, Volatile / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
chemical_list: D014151:Anti-Anxiety Agents; D000081008:Bicyclic Monoterpenes; D019208:Brain-Derived Neurotrophic Factor; D039821:Monoterpenes; D009822:Oils, Volatile; D012333:RNA, Messenger; D014446:Tyrosine 3-Monooxygenase; C005451:alpha-pinene
keywords: accumulation; anxiolytic-like effect; brain mRNA; inhaled administration; α-pinene