Aim: This study aimed to assess the changes in neuronal density in CA1 and CA3 regions in the hippocampus of young adulthood and middle age rat model after feeding by Ocimum sanctum ethanolic extract.

Materials and Methods: In this research, 30 male Wistar rats consist of young to middle-aged rats were divided into three groups (3, 6, and 9 months old) and treated with a different dosage of O. sanctum ethanolic extract (0, 50, and 100 mg/kg b.w.) for 45 days. Furthermore, cresyl violet staining was performed to analyze hippocampus formation mainly in CA1 and CA3 area. The concentrations of acetylcholine (Ach) in brain tissues were analyzed by enzyme-linked immunosorbent assay.

Results: In our in vivo models using rat model, we found that the administration of O. sanctum ethanolic extract with a dosage of 100 mg/kg b.w. for 45 days induced the density of pyramidal cells significantly in CA1 and CA3 of the hippocampus. These results were supported by an increase of Ach concentrations on the brain tissue.

Conclusion: The administration of O. sanctum ethanolic extract may promote the density of the pyramidal cells in the CA1 and CA3 mediated by the up-regulated concentration of Ach.

Keywords: acetylcholine, CA1, CA3, Ocimum sanctum.

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