The Effect Of Folate Deficiency On Weanling Rats' Learning And Memory

Purpose: To verify the effect of folate deficiency on weanling rats' leaming and memorythe relationship of hippocampal synaptosomal membran fluidity and the altetation ofweanling rats' lendng and memory was preliminarily studied .Our research was expectedto provide some zoological evidence to this effect on the aspect of membrane funtion.Metbod: 54 male weaIiling Sprague-Dawley rats were divided into three grouPs .Thefolate deficient group received an amino acid-defined diet(RHAA),the ad libitum controlgroup had the same diet suPplemented with folate of 8mg per kg diet, and the pair-fedcontrol group received the folate supplemented diet,but was individualy pair-fed to themean drily food consurnption of the folate deficient group .Body weight and food intakewere measured boce weekly. At the end of the second and sixth week of the experiment, 27rats,9 from each group,were tmdergone a Motris Waer Maze behavioral training for 5 dnys,an auo-video system recorded the escape latency and the swirtuning pattem. The serumfolate concentration and the fluorescence intensity of the hippocampal synaPtosomalmembrane(r value) marked by a fluorescent substance DPH, Which reflected the membranefluldity were also assayed. Correlation analysis was processed among serum folateconcentration and fluorescence intensity and the percentage of swinuning distance in theplatform quadrant.Results: Growth retardation and impaired food intake associated with FD could not bedemonstfated in the FD group rats until the end of the 3rd week (p<0. 05),While the pair-fedgroup gradually showed this retardation at the end of the 4th week .At the end of theexPerimellt the FD rats had weight loss, leaving the pair-fed group slighlyaffected(compared with ad libitum control group, p<0. 05). Decreased serum folate occurredat the end of the 2nd week of the experiment, without altefation of the other parameters. Atthe end of the 6th week, FD group rats had very low body weight and serum folateconcentration (P<0. 01), with the mean escape latency lengthened and the percentage ofswinuning districe in the platform quadran decreased. The fluorescence intensity of thehippocampal synaptosomal membrane increased, which implied reduced membranefluidity(P<0. 01). Correlation analysis results showed that the fluorescence intensity of thehippocampal synaptosomal membrane(r value)and the serum folate concentfation,meanescaPe latency and the percentage of switnming distance in the platform quadrant werekighly correlated(r=-0.527, p<0.05; r=-0.451, p<0.05; r=-0.579, p<0.05).Conclusion: 1. Folate deficiency could be produced in 6 weeks with reflned amino aciddich tha promoted maximum growth rate, it's an effective protocol to produce experimentalFD in young bomals within a short period of time. 2. Folate deficiency cou1d impair theledring and memory of weanling rats, the impairmeni was rather obvious at the 6th week. 3.Folate deficiency could reduce weanling rats' hiPPocarnpal synaptosomal membranefluidity.4. The reduction of hippocampal synaPtosomal membrane nuidity is Possibly oneof the mechanism of folate deficiency impairing the wealiling rats' ledring and memory...