Efeitos farmacológicos do extrato aquoso de Solidago chilensis Meyen em camundongos / Pharmacological effect of aqueous extract from Solidago chilensis Meyen on mice

Solidago chilensis Meyen (Asteraceae) é uma espécie nativa da América do Sul (Brasil) encontrada principalmente na região Sul do Brasil onde é conhecida popularmente como arnica-do-mato. Na medicina popular, ela é utilizada como diurética, cicatrizante, e anti-inflamatória. No presente trabalho, os efeitos farmacológicos do extrato aquoso das raízes de S. chilensis foram avaliados em modelos experimentais in vivo de atividade tipo-antidepressiva, antiinflamatória, antinociceptiva, e locomotora. O extrato (25, 100 e 250 mg kg-1) foi administrado por via oral 30 min antes dos experimentos comportamentais. Os resultados mostram que, nas doses utilizadas, o extrato aquoso de S. chilensis não apresentou atividade tipo-antidepressiva apesar de induzir efeitos analgésico e antiinflamatório significativos. Uma redução da atividade locomotora foi observada com a maior dose (250 mg kg-1) administrada, sugerindo efeito sobre o sistema nervoso central. Em conclusão, os resultados estão de acordo com a literatura acerca dos efeitos analgésicos e antiinflamatórios da planta, sugerindo também uma atividade do extrato de S. chilensis sobre o sistema nervoso central. Essas observações, porém, não excluem um possível efeito relaxante muscular periférico do extrato.

Solidago chilensis Meyen (Asteraceae) is a species native to South America (Brazil), found especially in the south region of Brazil, where it is commonly known as "arnica-do-mato". In folk medicine, it has been used as diuretic, healing and anti-inûammatory. In the present study, the pharmacological effects of aqueous extracts from roots of S. chilensis were assessed in vivo in experimental models for antidepressant, anti-inflammatory and locomotor-type activity. The extract (25, 50 and 250 mg kg-1) was administered by the oral route 30 minutes prior to behavioral tests. Results indicate that, at the employed levels, aqueous extract from S. chilensis did not show antidepressant-type activity although it induced significant analgesic and anti-inflammatory effects. A reduction in the locomotor activity was noted at the highest administered level (250 mg kg-1), suggesting an effect on the central nervous system. In conclusion, results agree with the literature about analgesic and anti-inflammatory effects of this plant, also suggesting an activity of S. chilensis extract on the central nervous system. These remarks, however, do not exclude a possible peripheral muscular relaxing effect of the extract.

Microbial mutagenicity studies with (Z)-1,3-dichloropropene.

This study has confirmed that the direct mutagenicity previously observed when S. typhimurium TA100 was treated with (Z)-1,3-dichloropropene (DCP) was in fact due to trace impurities. These impurities result from autoxidation of (Z)-1,3-DCP and have now been identified. Both (Z)- and (E)-2-chloro-3-(chloromethyl)oxiranes (DCP oxides) were identified as significant products during this autoxidation. The mutagenic impurities formed by autoxidation were completely removed by adsorption chromatography on silicic acid. (Z)-1,3-DCP purified in this way had no direct-acting mutagenicity towards S. typhimurium TA100. However, (Z)-1,3-DCP undergoes mono-oxygenase-catalysed conversion into bacterial mutagens in the presence of S9 fraction or washed microsomes from rat liver. The glutathione-linked conjugation systems of mammalian tissues provided efficient protection against this indirect mutagenic action. However, the low concentration of glutathione in standard bacterial mutagenicity assays limits the glutathione S-alkyl transferase-catalysed detoxification of (Z)-1,3-DCP and its primary bioactivation product(s). When the concentration of glutathione was adjusted to the normal physiological concentration, the mono-oxygenase-dependent mutagenic action of (Z)-1,3-DCP was virtually eliminated. These results therefore are consistent with the view that bacterial mutation assays are only qualitative indicators of potential mammalian genotoxicity.

Current status on the Florida Abate Monitoring program--susceptibility levels of three species of mosquitoes during 1984.

During 1984, larval susceptibility tests of temephos were performed on Aedes taeniorhynchus and Culex nigripalpus collected from the same general areas as in 1980-82, and the results compared to the susceptible laboratory strains. No resistance was detected against these two species. When strains of Culex quinquefasciatus from some new areas were tested against temephos, malathion, naled, fenthion and chlorpyrifos, their tolerance varied according to the insecticide tested and the origin of the strain. Some strains ranged from 1.6 to 43.0X more tolerant to temephos when compared to the West Florida Arthropod Research Laboratory strain (WFARL strain).