Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Junín 956, C1113AAD Buenos Aires, Argentina.
J Ethnopharmacol. 2012 Jul 13;142(2):401-6. doi: 10.1016/j.jep.2012.05.009. Epub 2012 May 17.
Lithrea molleoides (Vell.) Engl. (Anacardiaceae) is a medicinal plant commonly used in traditional medicine in South America.
In the present study, the in vivo antinociceptive effect of L. molleoides' aqueous extract and its isolated compounds has been investigated.
Antinociceptive activity was evaluated through writhing, formalin and hot plate tests in mice. The phytochemical analysis was performed.
The extract produced significant inhibition on nociception induced by acetic acid (ED50: 8.7 mg/kg, i.p.) and formalin (ED50: 7.7 mg/kg, i.p.) administered intraperitoneally and also orally. Yohimbine diminished the activity of the extract in the acetic acid test meanwhile haloperidol enhanced its effect. Two majority compounds, shikimic and vanillic acid were active in chemical nociceptive models used in this work, producing the highest inhibition of the writhing response at a dose of 30 mg/kg i.p. (55.4% and 57.1%, respectively) meanwhile at 100 mg/kg p.o. produced a slight response (23.3% and 23.9%, respectively).
These results suggest that L. molleoides' aqueous extract produced antinociception possibly related to the presence of shikimic and vanillic acid. The adrenergic and dopaminergic systems seem to be involved in the mechanism of antinociception of the extract.
Lithrea molleoides（Vell.）Engl.（漆树科）是一种药用植物，在南美洲的传统医学中被广泛使用。
本研究旨在研究 Lithrea molleoides 水提取物及其分离化合物的体内镇痛作用。
通过扭体、福尔马林和热板试验在小鼠体内评估镇痛活性。进行了植物化学分析。
提取物对腹腔内给予的乙酸（ED50：8.7mg/kg）和福尔马林（ED50：7.7mg/kg）引起的疼痛有显著抑制作用，也有口服作用。育亨宾减弱了提取物在乙酸试验中的活性，而氟哌啶醇增强了其作用。两种主要化合物，莽草酸和香草酸在本工作中使用的化学疼痛模型中具有活性，在 30mg/kg 腹腔内注射时产生最高的扭体反应抑制作用（分别为 55.4%和 57.1%），而在 100mg/kg 口服时产生轻微的反应（分别为 23.3%和 23.9%）。
这些结果表明，Lithrea molleoides 水提取物产生的镇痛作用可能与莽草酸和香草酸的存在有关。肾上腺素能和多巴胺能系统似乎参与了提取物的镇痛机制。
