Beijamini Venessa, Andreatini Roberto
Departamento de Farmacologia, Laboratório de Fisiologia e Farmacologia do Sistema Nervoso Central, Setor de Ciências Biológicas, Centro Politécnico, Universidade Federal do Paraná, P.O. Box 19031, 81531-990, PR, Curitiba, Brazil.
Pharmacol Res. 2003 Aug;48(2):199-207. doi: 10.1016/s1043-6618(03)00097-5.
Hypericum perforatum extract exhibits an antidepressant effect and since several antidepressant drugs are also effective on generalised anxiety disorder (GAD) and panic disorders (PD), H. perforatum may possess some anxiolytic/antipanic effect. Thus, the aim of the present study was to evaluate the putative antipanic/anxiolytic effect of standardised H. perforatum extract (LI 160) on rats tested in the elevated T-maze, an animal model of innate (panic) and learned (generalised) anxiety, at doses that exhibit antidepressant-like activity. H. perforatum (150, 300 and 500 mg/kg, administered orally 24, 18 and 1h before the test) decreased the immobility time in the forced swim test. Rats were treated orally with H. perforatum (150 or 300 mg/kg) or paroxetine (5mg/kg) 24, 18, and 1h before being tested in the elevated T-maze (subacute treatment). Immediately after this test, the animals were submitted to the open field to evaluate locomotor activity. Paroxetine was used as a positive control, since it was clinically effective in GAD and PD. Other groups of animals were submitted to the same drug treatment for 7 days (subchronic treatment). Paroxetine (5mg/kg) impaired inhibitory avoidance after subacute treatment, while subchronic administration increased one-way escape latency. Subacute treatment with H. perforatum (300 mg/kg) exerts a partial anxiolytic-like effect in the inhibitory avoidance task. Repeated administration of H. perforatum (300 mg/kg) induced an anxiolytic effect (decreased inhibitory avoidance) and an antipanic effect (increased one-way escape). No effect on locomotor activity was found with any treatment. Thus, the results suggest that H. perforatum extract could exert an anxiolytic and antipanic effect.
贯叶连翘提取物具有抗抑郁作用，而且由于几种抗抑郁药物对广泛性焦虑症（GAD）和惊恐障碍（PD）也有效，贯叶连翘可能具有一些抗焦虑/抗惊恐作用。因此，本研究的目的是评估标准化贯叶连翘提取物（LI 160）在高架T迷宫实验中对大鼠的假定抗惊恐/抗焦虑作用，高架T迷宫是一种先天性（惊恐）和习得性（广泛性）焦虑的动物模型，使用具有抗抑郁样活性的剂量。贯叶连翘（150、300和500mg/kg，在测试前24、18和1小时口服给药）减少了强迫游泳实验中的不动时间。在高架T迷宫实验（亚急性治疗）前24、18和1小时，给大鼠口服贯叶连翘（150或300mg/kg）或帕罗西汀（5mg/kg）。该实验结束后，立即将动物放入旷场实验以评估运动活性。帕罗西汀用作阳性对照，因为它在GAD和PD的临床治疗中有效。其他组动物接受相同药物治疗7天（亚慢性治疗）。亚急性治疗后，帕罗西汀（5mg/kg）损害了抑制性回避，而亚慢性给药增加了单向逃避潜伏期。贯叶连翘（300mg/kg）亚急性治疗在抑制性回避任务中发挥了部分抗焦虑样作用。重复给予贯叶连翘（300mg/kg）产生了抗焦虑作用（减少抑制性回避）和抗惊恐作用（增加单向逃避）。任何治疗对运动活性均无影响。因此，结果表明贯叶连翘提取物可发挥抗焦虑和抗惊恐作用。
