Studies Of The Effects On Improving Learning And Memory And The Toxicological Assessment Of Extract Of Wallnut In Mice And Rats

object: To investigate the effects of extract of walnut on improving learning and its toxicityMethods: Acute toxicity test, 30 days feeding test were carried out to judge the general toxicity of the extract of walnut . The Ames test, micronucleus test of bone narrow cell, chromosome aberration test in mice testicle cells were used to detect it genetic toxicities. After female mice were treated orally in the different doses of the extract of walnut for 30 days ,they were tested in the one-trail passive avoidance response and Morris water maze task respectively. Then ACHE (acetylcholinesterase ), NO(nitrous oxide) and protein of brain were measured.Results: The orally LD50 of the extract of walnut is more than 10g/kg.bw; All the biochemistry indexs are normal in subacute toxicity test, Furthermore, these index has no significantly difference and the ratio of organs and weightalso has no significant difference. The result of Ames test indicate that the negative group and the dose groups have no difference, However, these groups have significant difference compared with the positive group. The same results were observed in micronucleus test, chromosome aberration test in testicle cell and single cell gel electrophoresis assays. The middle dose group has lest error times and the latency is shortest. The dose response relationship of the error times in the one-trail passive avoidance response test is "U" change. NO and AchE levels of the brains increase with doses of the extract of walnuts. NO level of high dose group has difference with the other groups.Conclusion: It is suggested that extract of walnut was safe and could improve learning and memory at some range doses.