Vollala Venkata Ramana, Upadhya Subramanya, Nayak Satheesha
Rajiv Gandhi Institute of Medical Sciences, Adilabad, Andhra Pradesh, India.
Rom J Morphol Embryol. 2011;52(3):879-86.
Bacopa monniera (BM), a traditional Ayurvedic medicine has been used in treatment for a number of disorders, particularly those involving anxiety, intellect and poor memory. The current study examined the effects of standardized extract of Bacopa monniera on the dendritic morphology in adult rats of hippocampal CA3 neurons, one of the regions concerned with learning and memory.
Adult Wistar (2.5-month-old) rats were designated into 2-, 4- and 6-week treatment groups. Rats in each of these groups were divided into 20 mg/kg, 40 mg/kg and 80 mg/kg dose groups (n=8 for each dose). These rats along with age-matched control rats were then subjected to spatial learning (T-maze) and passive avoidance tests. Subsequent to the T-maze and passive avoidance tests, these rats were killed by decapitation, brains were removed and hippocampal neurons were impregnated with silver nitrate (Golgi staining). Hippocampal CA3 neurons were traced using camera lucida. Dendritic branching points (a measure of dendritic arborization) and dendritic intersections (a measure of dendritic length) were quantified. These data were compared with control rats.
The results showed improvement in spatial learning performance and enhanced memory retention in rats treated with BM extract. There was a significant increase in the dendritic intersections and dendritic branching points along the length of both apical and basal dendrites in rats treated with BM extract for four and six weeks. However, the rats treated with BM extract for two weeks did not show any significant change in hippocampal CA3 neuronal dendritic arborization. We conclude that constituents present in BM extract have neuronal dendritic growth stimulating properties.
假马齿苋（Bacopa monniera，BM）是一种传统的阿育吠陀药物，已被用于治疗多种疾病，特别是那些涉及焦虑、智力和记忆力差的疾病。本研究考察了假马齿苋标准化提取物对成年大鼠海马CA3神经元树突形态的影响，海马CA3神经元是与学习和记忆相关的脑区之一。
将成年Wistar大鼠（2.5月龄）分为2周、4周和6周治疗组。每组大鼠再分为20mg/kg、40mg/kg和80mg/kg剂量组（每组n = 8）。然后将这些大鼠与年龄匹配的对照大鼠一起进行空间学习（T迷宫）和被动回避试验。在T迷宫和被动回避试验后，断头处死这些大鼠，取出大脑，用硝酸银浸染海马神经元（高尔基染色）。用显影仪追踪海马CA3神经元。对树突分支点（衡量树突分支程度）和树突交叉点（衡量树突长度）进行量化。将这些数据与对照大鼠进行比较。
结果显示，用BM提取物处理的大鼠空间学习能力提高，记忆保持增强。用BM提取物处理4周和6周的大鼠，其顶端和基底树突长度上的树突交叉点和树突分支点均显著增加。然而，用BM提取物处理2周的大鼠海马CA3神经元树突分支没有显示出任何显著变化。我们得出结论，BM提取物中的成分具有刺激神经元树突生长的特性。
