Evaluation of the Effects of Lactational Exposure to Hyoscyamine Fraction of Datura stramonium L. Seeds on Learning and Memory in Wistar Rats (Rattus norvegicus)

Abstract

Background: Datura stramonium (D. stramonium), is a family member of Solanaceae, an annual plant known for its medicinal and toxic properties. Aims and Objectives: The study was designed to determine whether lactational exposure to hyoscyamine fraction of Datura stramonium L. (D. stramonium) seeds affect the cognitive, spatial learning and memory functions of the hippocampus in Wistar rats at adulthood. Materials and Methods: Fresh seeds of D. stramonium L. were procured, macerated and fractionated. Eight (8) Wistar rats weighed 150-250 grams of equal gender were used for the study. The rats were mated and divided into control and treatment groups. Equivalent body weight of normal saline and 400 mg/kgbwt of hyoscyamine fraction were orally administered to the breastfeeding rats respectively on lactational days (LD) 1-21. At adulthood, the rats were subjected to neurobehavioural tests using novel objects recognition (NORT) and Morris water maze (MWM) respectively. The data obtained were expressed as mean ± SEM, independent two samples t-test and General Linear Model (GLM) repeated-measures ANOVA with Fisher's multiple comparisons post-hoc tests were used to show the mean differences using Minitab 17 (LLC., U.K.) statistical package software. P Results: A significant increase in the meantime of exploration between the groups (p = 0.049) was observed during the NORT. No statistically significant increase (p = 0.626) in the meantime to locate the escape platform between the groups during the MWM test. The CA1 region of the treated group showed mild nuclear hyperchromasia, cytoplasmic vacuolations and pyknosis. Conclusion: In conclusion, exposure to hyoscyamine fraction of D. stramonium L. seeds at lactation caused neuronal lesions in the CA1 region, impaired novel objects recognition but not spatial learning and memory in Wistar rats at adulthood.