Effect of Bacopa monniera on amygdaloid neurons Vollala VR et al. CLINICS 2011;66(4):663-671 Table 4 - Basolateral amygdaloid neuronal dendritic branching points at different concentric zones and total number of branching points (6-week duration). Groups NC GAC BM 20 mg/kg BM 40 mg/kg BM 80 mg/kg n 8 8 8 8 8 0-20 1.43 ¡ 0.45 1.56 ¡ 0.42 1.65 ¡ 0.64 3.16 ¡ 0.70*** 2.92 ¡ 0.81$$$ 20-40 2.68 ¡ 0.56 2.76 ¡ 0.61 3.86 ¡ 0.67# 5.26 ¡ 0.75*** 5.08 ¡ 0.83$$$ Concentric zones, mm 40-60 1.12 ¡ 0.32 1.08 ¡ 0.43 1.93 ¡ 0.64# 2.92 ¡ 0.55*** 2.85 ¡ 0.61$$$ 60-80 0.52 ¡ 0.42 0.48 ¡ 0.39 0.61 ¡ 0.41 1.40 ¡ 0.62* 1.28 ¡ 0.54$ 80-100 0.13 ¡ 0.10 0.11 ¡ 0.09 0.23 ¡ 0.13 0.46 ¡ 0.22* 0.42 ¡ 0.29$ Total number of branching points 5.91 ¡ 1.05 6.01 ¡ 1.10 8.15 ¡ 0.98## 13.21 ¡ 1.20*** 12.55 ¡ 1.35$$$ BM, Bacopa monniera; GAC, gum acacia control; NC, normal control. Note: Each value represents mean ¡ standard deviation. NC vs. BM 20 mg/kg: # P,0.05, ## P,0.01; NC vs. BM 40 mg/kg: * P,0.05, *** P,0.001; NC vs. BM 80 mg/kg: $ P,0.05, $$$ P,0.001. study, the enhanced passive avoidance learning and memory in the rats treated with BM supported the functionality of the increased dendritic arborization in amygdaloid neurons of these rats. Dendrites are the major determinants of how neurons integrate and process incoming information; therefore, they play a vital role in the functional properties of neuronal circuits. The functional organization of the various parts of the brain is dynamic and can change in response to experimental manipulations. Alterations in synaptic func- tion, neuronal membrane properties and axonal trajectories are associated with these changes. The BM extract used in this study may play a role in these manipulations and lead to dendritic alterations. The BM extract may stimulate the release of neuromodu- lators that alter the activity of neurotransmitters that are involved in learning and memory, which thereby contri- butes to enhanced learning and memory. Our earlier study showed that BM extract treatment in rats improved spatial learning performance and enhanced memory retention.34 Similar changes in the amygdala form the basis for improved memory retention. CONCLUSION In conclusion, the results of our experiment suggested that BM extract treatment in rats with higher doses for longer periods induced structural changes in basolateral amygdaloid neurons that improved learning and memory. ACKNOWLEDGMENTS The authors sincerely thank M/s. Natural Remedies Private Limited for supplying the BM extract and Manipal University (MU) for providing the experimental facilities to perform this work. REFERENCES 1. Singh HK, Dhawan BN. Effect of Bacopa monniera (Brahmi) extract on avoidance responses in rats. 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