[Effects of traditional Chinese herbal medicine on the neurobehavioral manifestations and the activity of dopamine D2 receptor in corpora striatum of rats with levodopa-induced dyskinesias].
OBJECTIVE
To explore the effect of traditional Chinese herbal medicine (TCM) for nourishing liver and kidney, clearing meridians and removing toxic substances, on the neurobehavioral manifestations and the activity of the dopamine D2 receptor in rat with levodopa-induced dyskinesias (LID).


METHODS
The rat model of Parkinson's disease (PD) was established by injecting 6-hydroxydopamine (6-OHDA) into right substantia nigra of brain, then, the model of LID in rat was produced by injecting levodopa (LD) and benserazide for 4 weeks. The rats were divided into normal control group, 4-week LD treated group, 4-week LD plus TCM treated group, 8-week LD treated group, and 8-week LD plus TCM treated group, and the effect of the TCM on neurobehavioral manifestations was observed. The radioligand binding assay (RLBA) and Scatchard drawing were used to measure the maximal binding capacity of receptor (Bmax) and equilibrium dissociation constant (KD) of the dopamine D2 receptor in corpora striatum.


RESULTS
Compared with the 4-week LD treated group and 8-week LD treated group, TCM could decrease abnormal involuntary movement scores of the rats with LID; the RLBA revealed that the dopamine D2 receptor Bmax significantly increased (P<0.05, P<0.01) and the KD significantly decreased (P<0.05).


CONCLUSIONS
TCM can improve the activity of the dopamine D2 receptor and relieve the symptoms of LID.
Department of Neurology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai 200032, China. ycanxing@hotmail.com
Can-Xing
CX
Yuan
Qing
Q
Ye
Jie
J
Wang
Yan
Y
Zhang
Chong-Gang
CG
Yuan
D000818:Animals; D001545:Benserazide; D003342:Corpus Striatum / Q000378:metabolism*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology / Q000627:therapeutic use; D020820:Dyskinesias / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D016627:Oxidopamine; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000150:complications; D008517:Phytotherapy; D051381:Rats; D017207:Rats, Sprague-Dawley; D017448:Receptors, Dopamine D2 / Q000187:drug effects / Q000378:metabolism*
D004365:Drugs, Chinese Herbal; D017448:Receptors, Dopamine D2; D007980:Levodopa; D001545:Benserazide; D016627:Oxidopamine