title: [Study on effects of Corydalis yanhusuo and L-THP on dopamine of reward circuitry in conditioned place preference rats and comparison].
abstract: OBJECTIVE
  To study and compare the effect of Corydalis yanhusuo and L-THP on dopamine neurotransmitter and D2 receptor of reward circuitry in various cerebral areas of conditioned place preference model rats and the comparison of their effects.
  
  
  METHODS
  The CPP model was established by injecting morphine in rats with increasing doses for 10 days. The initial dose of 10 mg x kg(-1), and the final dose of 100 mg x kg(-1), with 10 mg x kg(-1) increased each day. At 48 h after the final training, CPP was adopted to detect the successful establishment of the model. On the same day (12 d), they were orally administered with 2, 1, 0.5 g x kg(-1) C. yanhusuo (containing 0.153, 0.077 and 0.038 mg L-THP) and L-THP (3.76, 1.88, 0.94 mg x kg(-1)) for six days. On 18 d, CPP test was performed again. Next day, HPLC was adopted to determine the content of dopamine neurotransmitters of reward circuitry in VTA-NAc-PFC; Immunohistochemistry and Western blotting were adopted to detect the expression of D2 receptors.
  
  
  RESULTS
  Compared with the physiological saline treatment group, C. yanhusuo (2, 1 g x kg(-1)) and L-THP (3.76, 1.88 mg x kg(-1)) groups showed that rats stayed in a notably shorter period in white boxes (morphine-accompanied boxes) (P < 0.01 or P < 0.05), and revealed a remarkably lower dopamine content in VTA, NAc and PFC and the significant increase in the expression of D2 receptor (P < 0.01 or P < 0.05).
  
  
  CONCLUSIONS
  The down-regulation of the increased dopamine content in reward nervous circuitry and the up-regulation of the expression of D2 receptor may be one of mechanisms of C. yanhusuo and L-THP in accelerating the recession of morphine's CPP effect Regarding the inhibition of morphine's CPP effect and the effect on dopamine system, the effect of C. yanhusuo traditional Chinese medicine containing one-fold L-THP monomer is equal to that of the independent application of around 24-fold L-THP monomer.
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Shou-Yang
authors.initials: SY
authors.lastname: Yu
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Pei-Run
authors.initials: PR
authors.lastname: Yang
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Qian
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Ming-Song
authors.initials: MS
authors.lastname: Wu
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Wei-Feng
authors.initials: WF
authors.lastname: Bai
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Tu
authors.affiliation: Research Room of Cytogiology and Genetics, Zunyi Medical College, Zunyi 563000, China.
authors.forename: Su-Yuan
authors.initials: SY
authors.lastname: Luo
mesh_terms: D000818:Animals; D001600:Berberine Alkaloids / Q000008:administration & dosage*; D001921:Brain / Q000187:drug effects / Q000378:metabolism / Q000503:physiopathology*; D003216:Conditioning, Operant / Q000187:drug effects*; D031311:Corydalis / Q000737:chemistry*; D004298:Dopamine / Q000378:metabolism*; D006801:Humans; D008297:Male; D009020:Morphine / Q000009:adverse effects*; D010936:Plant Extracts / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000235:genetics / Q000378:metabolism; D019966:Substance-Related Disorders / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism / Q000523:psychology
chemical_list: D001600:Berberine Alkaloids; D010936:Plant Extracts; D017448:Receptors, Dopamine D2; C014215:tetrahydropalmatine; D009020:Morphine; D004298:Dopamine