Serotonergic mediation of the antidepressant-like effect of the green leaves odor in mice.
The green odor (GO) that emanates from green leaves has been observed to have many physiological actions in mammals and may be associated with a healing effect in humans. This study examined the effect of GO (we used a mixture of cis-3-hexenol and trans-2-hexenal) on behavior in the forced swim test (FST) of depression in mice. Exposure of GO showed the antidepressant-like effect in the FST, i.e., a significant decrease in immobility time and increase in swimming time, but no change in climbing time. The behavioral responses of GO-exposed animals to FST were similar to those observed for animals given citalopram, which is a selective serotonin reuptake inhibitor. In contrast, desipramine, which is a selective noradrenaline reuptake inhibitor, decreased immobility time and increased climbing time without affecting swimming time. To examine the involvement of the serotonergic system in mediating the antidepressant-like action of GO, we performed further FST examinations in which GO-exposed mice were treated with p-chlorophenylalanine (PCPA). Prior PCPA administration induced depletion of central 5-HT in the brain and completely diminished the GO effect on the behavioral responses seen during the FST. No changes in locomotor activity after GO inhalation were observed. These results indicate that acute exposure to GO has an antidepressant-like effect that may involve the serotonergic system.
Nakatomi
Yasuhito
Y
Department of Psychiatry, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Yokoyama
Chihiro
C
Kinoshita
Seijiro
S
Masaki
Daiki
D
Tsuchida
Hideto
H
Onoe
Hirotaka
H
Yoshimoto
Kanji
K
Fukui
Kenji
K
D000818:Animals; D000928:Antidepressive Agents / Q000627:therapeutic use*; D001522:Behavior, Animal / Q000187:drug effects; D001923:Brain Chemistry / Q000187:drug effects; D015283:Citalopram / Q000627:therapeutic use; D003863:Depression / Q000188:drug therapy*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D010134:Fenclonine / Q000008:administration & dosage; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009043:Motor Activity / Q000187:drug effects; D009812:Odorants; D018515:Plant Leaves / Q000737:chemistry*; D012701:Serotonin / Q000378:metabolism*; D012702:Serotonin Antagonists / Q000008:administration & dosage; D013550:Swimming
D000928:Antidepressive Agents; D012702:Serotonin Antagonists; D015283:Citalopram; D012701:Serotonin; D010134:Fenclonine