Enhancement of Hippocampal CA3 Neuronal Dendritic Arborization by Glycyrrhiza glabra root extract Treatment in Wistar Albino Rats

BACKGROUND: In the traditional system of medicine, the roots and rhizomes of Glycyrrhiza glabra (Gg) (family: Leguminosae) have been in clinical use for centuries. AIM: In the present study, we investigated the role of aqueous extract of root of Gg treatment on the dendritic morphology of hippocampal Cornu Ammonis area three (CA3) neurons, one of the regions concerned with learning and memory, in 1- month- old male Wistar albino rats. MATERIALS AND METHODS: The aqueous extract of root of Gg was administered orally in four doses (75, 150, 225 and 300 mg/kg) for 4 weeks. After the treatment period, all experimental animals were subjected to spatial learning (Morris water maze, Hebb-William's maze and elevated plus maze) tests. At the end of the spatial memory tests, the rats were deeply anesthetized with Pentobarbitone and killed their brains were removed rapidly and fixed in rapid Golgi fixative. Hippocampal CA3 neurons were traced using camera lucida, and dendritic arborization and intersections were quantified. These data were compared to those of age-matched control rats. RESULTS: The aqueous root extract of Gg in the dose of 150 and 225 mg/kg/p.o showed a significant (P < 0.01) enhancement of dendritic arborization (dendritic branching points) and dendritic intersections along the length of both apical and basal dendrites in hippocampal (CA3) pyramidal neurons is comparable to control. CONCLUSION: Based on our results obtained, we conclude that constituents present in aqueous root extract of Gg have neuronal dendritic growth stimulating properties.