Efeito do hypericum perforatum, em preparação homeopática e fitoterápica, sobre o desamparo aprendido em ratos / Effect of hypericum perforatum, in homeopathic and phytotherapic preparation, upon learned helplessness in rats

AUTOR(ES)
DATA DE PUBLICAÇÃO

2006

RESUMO

Alternative treatments for the human depression have been conducted in the homeopathy and phytoterapy, through Hypericum perforatum (Hp), dynamized or extract, respectively. Experimentally, learned helplessness is proposed as an animal model of depression, which permits its use to test the effects of potential antidepressants. Two experiments were conducted to investigate whether Hp, either in homeophatic and or in phytotherapic preparation, can prevent the occurrence of learned helplessness in animals. In the Experiment 1, 96 male Wistar rats were divided into 12 groups (n=8) exposed to treatment and test phases, separated by 24 hours. Groups were divided into triads exposed to controllable shocks (C), uncontrollable shocks (I) or no shocks (N). After that, Hp was administered orally (five drops) to each triad in one of three dynamizations – 30CH, 200CH and 0CH (vehicle - hydroalcoholic solution 5%) – three times: 0, 19, and 23 hours after treatment with shocks. The fourth triad didn’t receive drug (sd) and it was used in both experiments. In the test phase, all the animals were exposed to an escape contingency in a shuttlebox. In the Experiment 2, 72 rats were divided into 9 groups (n=8). Equipments were the same and procedure was similar to Experiment 1, with the exception of drug administration. Extract of Hp was administered, i.p., 1 ml/kg, in one of three concentrations for each triad – 0 mg/kg (vehicle – hydroalcoholic solution 5%), 15 mg/kg and 30 mg/kg - 22 hours after treatment with shocks. Results showed that, among the groups that were not administered pharmacological treatment, only Group I did not learn to escape, an indication of learned helplessness. In Experiment 1, among the groups that were administered Hp in homeopathic preparation, groups N and C were not affected, while response latencies for groups I decreased, with a stronger effect with 200CH. Treatment with 0CH caused a small reduction of general latencies, although it wasn’t suficient to prevent helplessness. In Experiment 2, results showed that Hp in phytotherapic administration didn’t affect groups N and C, while the latencies of Group I were reduced, with a stronger effect with Hp 0mg/kg. These data suggest that the vehicle wasn’t inert pharmacologically, which casts doubt on the results that involved Hp. In conclusion, more studies will be necessary to attest the efficacy of homeopathic and phytotherapic treatment.

ASSUNTO(S)

phytotherapy fitoterapia desamparo aprendido antidepressant drugs homeopatia learned helplessness homeopathy drogas antidepressivas

Documentos Relacionados