title: The ameliorating effects of acute and chronic administration of LiuWei Dihuang Wang on learning performance in rodents.
abstract: The ameliorating effects of LiuWei Dihuang Wang (LDW) after single, one-week or two-week treatment of scopolamine (SCOP)-induced and p-chloroamphetamine (PCA)-induced amnesia by using the passive avoidance task and the facilitatory effects on two-way active avoidance performance in rats were studied. LDW (2 g/kg) after single treatment significantly prolonged the shortened step-through latency induced by SCOP and PCA. Then, SCOP- and PCA-induced amnesia was reversed by 1 and 0.1-1 g/kg LDW with one-week consecutive treatment respectively. For two-week consecutive treatment with LDW, the reversal from SCOP- and PCA-induced amnesia required only 0.01 g/kg. However, the rats treated with LDW only at 0.5, but not 0.01-0.1 g/kg, before or after each training session showed an increasing number of avoidances and a decreasing number of escapes on days 2-5 of learning. LDW at any dose alone did not influence the step-through latency in the training trial produced by non-shock rats, the motor activity and pentobarbital-induced hypnosis in rodents. These results suggest that LDW possesses the anti-amnestic and cognitive-enhancing activities related to the memory processes, and these activities were parallel to treatment duration and dependent on the learning models.
authors.affiliation: Institute of Chinese Pharmaceutical Sciences, China Medical College, Taichung, Taiwan, ROC.
authors.forename: Ming-Tsuen
authors.initials: MT
authors.lastname: Hsieh
authors.forename: Sung-Jen
authors.initials: SJ
authors.lastname: Cheng
authors.forename: Li-Wei
authors.initials: LW
authors.lastname: Lin
authors.forename: Wen-Hsin
authors.initials: WH
authors.lastname: Wang
authors.forename: Chi-Rei
authors.initials: CR
authors.lastname: Wu
mesh_terms: D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects / Q000502:physiology; D004305:Dose-Response Relationship, Drug; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage*; D004924:Escape Reaction / Q000187:drug effects* / Q000502:physiology; D007858:Learning / Q000187:drug effects* / Q000502:physiology; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004365:Drugs, Chinese Herbal