Plant Foods for Human Nutrition

, Volume 66, Issue 4, pp 335–340 | Cite as

Effects of Walnuts (Juglans regia) on Learning and Memory Functions

  • Saida Haider
  • Zehra Batool
  • Saiqa Tabassum
  • Tahira Perveen
  • Sadia Saleem
  • Fizza Naqvi
  • Huma Javed
  • Darakhshan J. Haleem
Original Paper

Abstract

Walnut has been regarded as a health food that is delicious and nutritious. Both preventive and therapeutic effects of walnut are well documented. Walnuts are rich in omega-3 fatty acids that are reported to have beneficial effects on brain function. The present work was designed to evaluate the effects of walnuts on learning and memory in male rats. The effect of oral intake of walnut was also monitored on food intake. Walnut was given orally to rats for a period of 28 days. Memory function in rats was assessed by elevated plus maze (EPM) and radial arm maze (RAM). A significant improvement in learning and memory of walnut treated rats compared to controls was observed. Walnut treated rats also exhibited a significant decrease in food intake while the change in growth rate (in terms of percentage) remained comparable between the two groups. Analysis of brain monoamines exhibited enhanced serotonergic levels in rat brain following oral intake of walnuts. The findings suggest that walnut may exert its hypophagic and nootropic actions via an enhancement of brain 5-HT metabolism.

Keywords

Elevated plus maze Hypophagic action Nootropic substance Radial arm maze Serotonin Walnut 

Abbreviations

5-HT

5-hydroxy tryptamine

5-HIAA

5-hydroxy indole acetic acid

ALA

Alpha linolenic acid

EPA

Eicosapentaenoic acid

EPM

Elevated plus maze

HPLC-EC

High performance liquid chromatography with electrochemical detection

LA

Linoleic acid

RAM

Radial arm maze

TRP

Tryptophan

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Saida Haider
    • 1
  • Zehra Batool
    • 1
  • Saiqa Tabassum
    • 1
  • Tahira Perveen
    • 1
  • Sadia Saleem
    • 1
  • Fizza Naqvi
    • 1
  • Huma Javed
    • 1
  • Darakhshan J. Haleem
    • 1
  1. 1.Neurochemistry and Biochemical Neuropharmacology Research Unit, Department of BiochemistryUniversity of KarachiKarachiPakistan

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