Department of Pharmacology and Therapeutics, Ahmadu Bello University, Zaria, Nigeria.
J Ethnopharmacol. 2012 May 7;141(1):128-33. doi: 10.1016/j.jep.2012.02.010. Epub 2012 Feb 14.
Securinega virosa is a commonly used medicinal plant in African traditional medicine in the management of epilepsy and mental illness. Previous studies in our laboratory showed that the crude methanol root bark extract of the plant possesses significant behavioral effect in laboratory animals. In an attempt to isolate and characterize the biological principles responsible for the observed activity, this study is aimed at evaluating the central depressant activity of the butanol fraction of the methanol root bark extract of Securinega virosa.
The medial lethal dose of the butanol fraction was estimated using the method of Lorke. Preliminary phytochemical screening was conducted on the butanol fraction using standard protocol. The behavioral effect of the butanol fraction (75, 150 and 300mg/kg) was evaluated using diazepam induced sleep test, hole-board test, beam walking assay, staircase test, open field test and elevated plus maze assay, all in mice.
The median lethal dose of the butanol fraction was estimated to be 1256.9mg/kg. The preliminary phytochemical screening revealed the presence of tannins, saponins, alkaloids, flavonoids, cardiac glycosides, similar to those found in the crude methanol extract. The butanol fraction significantly (P<0.001) reduced the mean onset of sleep in mice and doubled the mean duration of sleep in mice at the dose of 75mg/kg. The butanol fraction and diazepam (0.5mg/kg) significantly (P<0.01-0.001) reduced the number of head dips in the hole-board test suggesting sedative effect. The sedative effect of the butanol fraction was further corroborated by its significant (P<0.01-0.001) reduction of the number of step climbed and rearing in the staircase test. The butanol fraction did not significantly increase the time taken to complete the task and number of foot slips in the beam walking assay, suggesting that it does not induce significant motor coordination deficit. Diazepam (2mg/kg), the standard agent used significantly (P<0.01) increased the number of foot slips. In the open field test, the butanol fraction significantly reduced the number of square crossed as well as the number of rearing. However, the butanol fraction did not significantly alter the behavior of mice in the elevated plus maze assay, while diazepam (0.5mg/kg) significantly (P<0.05) increased the time spent in the open arm and reduced the number of closed arm entry.
The findings of this study suggest that the butanol fraction of Securinega virosa root bark contains some bioactive principles that are sedative in nature.
ETHNOPHARMACOLOGICAL 相关性：Securinega virosa 是非洲传统医学中一种常用于治疗癫痫和精神疾病的药用植物。我们实验室的先前研究表明，该植物的甲醇根皮粗提物对实验动物具有显著的行为作用。为了分离和表征负责观察到的活性的生物原则，本研究旨在评估 Securinega virosa 的甲醇根皮的正丁醇部分的中枢镇静活性。
使用 Lorke 方法估算正丁醇部分的中致死剂量。使用标准方案对正丁醇部分进行初步植物化学筛选。使用地西泮诱导的睡眠试验、洞板试验、梁行走试验、楼梯试验、旷场试验和高架十字迷宫试验评估正丁醇部分（75、150 和 300mg/kg）的行为效应，所有这些试验均在小鼠中进行。
正丁醇部分的中致死剂量估计为 1256.9mg/kg。初步植物化学筛选显示存在单宁、皂苷、生物碱、类黄酮、强心苷，类似于在甲醇粗提物中发现的那些。正丁醇部分在 75mg/kg 剂量下显著（P<0.001）降低了小鼠的平均入睡潜伏期，并使小鼠的平均睡眠时间增加一倍。正丁醇部分和地西泮（0.5mg/kg）显著（P<0.01-0.001）减少了洞板试验中的头浸次数，提示具有镇静作用。正丁醇部分在楼梯试验中显著（P<0.01-0.001）减少了爬升和后蹬的次数，进一步证实了其镇静作用。正丁醇部分在梁行走试验中没有显著增加完成任务所需的时间和脚步失误次数，表明它不会引起明显的运动协调缺陷。标准药物地西泮（2mg/kg）显著（P<0.01）增加了脚步失误次数。在旷场试验中，正丁醇部分显著减少了穿越的正方形数量以及后蹬的次数。然而，正丁醇部分在高架十字迷宫试验中没有显著改变小鼠的行为，而地西泮（0.5mg/kg）显著（P<0.05）增加了进入开放臂的时间并减少了进入封闭臂的次数。
本研究的结果表明，Securinega virosa 根皮的正丁醇部分含有一些具有镇静作用的生物活性成分。
