title: Role for monoaminergic systems in the antidepressant-like effect of ethanol extracts from Hemerocallis citrina.
abstract: BACKGROUND
  Hemerocallis citrina, a traditional herbal medicine, has been used for the improvement of emotions in Eastern-Asia countries.
  
  
  OBJECTIVE
  Herein, we explored the antidepressant-like effect and its monoaminergic mechanism of the ethanol extracts from Hemerocallis citrina (HCE).
  
  
  METHODS
  Effect of HCE (90, 180 and 360 mg/kg, p.o.) on the immobility time was assessed in the mouse forced swim test (FST) and tail suspension test (TST), and locomotor activity was evaluated in the open-field test (OFT). Additionally, the monoamine neurotransmitters serotonin (5-HT), noradrenaline (NA) and dopamine (DA) levels involved in the antidepressant-like effect of HCE were also measured in the mice brain regions of frontal cortex and hippocampus.
  
  
  RESULTS
  HCE (90, 180 and 360 mg/kg, p.o.) administration significantly reduced the immobility time in both the FST and TST without accompanying changes in locomotor activity in the OFT. The pretreatment of mice with WAY 100635 (0.1 mg/kg, s.c., a 5-HT(1A) receptor antagonist), cyproheptadine (3 mg/kg, i.p., a 5-HT(2) receptor antagonist), prazosin (62.5 μg/kg, i.p., an α(1)-adrenoceptor antagonist), yohimbine (1 mg/kg, i.p., an α(2)-adrenoceptor antagonist), propranolol (5 mg/kg, i.p., a β-adrenoceptor antagonist) or sulpiride (50 mg/kg, i.p., a dopamine D(2) receptor antagonist), but not SCH23390 (0.05 mg/kg, s.c., a dopamine D(1) receptor antagonist) prevented the antidepressant-like effect of HCE (360 mg/kg, p.o.) in the TST. In addition, HCE enhanced 5-HT and NA levels in the frontal cortex and hippocampus as well as elevated DA levels in the frontal cortex.
  
  
  CONCLUSIONS
  The results indicate that the antidepressant-like effect of HCE is dependent on the serotonergic (5-HT(1A) and 5-HT(2) receptors), noradrenergic (α(1)-, α(2)- and β-adrenoceptors) and dopaminergic (D(2) receptor) systems as well as the elevation of 5-HT, NA and DA levels in the mouse brain.
authors.affiliation: Department of Chemical and Pharmaceutical Engineering, College of Chemical Engineering, Huaqiao University, Xiamen, Fujian Province, PR China.
authors.forename: Lan
authors.initials: L
authors.lastname: Gu
authors.forename: Yan-Jun
authors.initials: YJ
authors.lastname: Liu
authors.forename: Yao-Bin
authors.initials: YB
authors.lastname: Wang
authors.forename: Li-Tao
authors.initials: LT
authors.lastname: Yi
mesh_terms: D000322:Adrenergic Agonists / Q000494:pharmacology / Q000627:therapeutic use; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology / Q000627:therapeutic use; D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001522:Behavior, Animal / Q000187:drug effects; D001921:Brain / Q000378:metabolism*; D003863:Depression / Q000188:drug therapy* / Q000378:metabolism; D015259:Dopamine Agents / Q000494:pharmacology / Q000627:therapeutic use; D031421:Hemerocallis; D019417:Hindlimb Suspension; D046353:Immobility Response, Tonic / Q000187:drug effects; D008124:Locomotion / Q000187:drug effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D018377:Neurotransmitter Agents / Q000494:pharmacology / Q000627:therapeutic use*; D009638:Norepinephrine / Q000378:metabolism; D008517:Phytotherapy; D010936:Plant Extracts / Q000494:pharmacology / Q000627:therapeutic use; D017982:Receptors, Biogenic Amine / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism; D013550:Swimming
chemical_list: D000322:Adrenergic Agonists; D000317:Adrenergic alpha-Antagonists; D000928:Antidepressive Agents; D015259:Dopamine Agents; D018377:Neurotransmitter Agents; D010936:Plant Extracts; D017982:Receptors, Biogenic Amine; D012701:Serotonin; D009638:Norepinephrine