The oil of the fruits of Euterpe oleracea Mart., Arecaceae (OEO), was evaluated in models of inflammation and hyperalgesia in vivo to study its effects on these conditions. The experimental models contained the writhing test in mice, rat paw edema, granuloma test in rats, vascular permeability in rats, cell migration to the peritoneal cavity in rats and ear erythema induced by croton oil in mice. Doses of 500, 1000 and 1500 mg/kg of OEO were administered orally. The observed number of writhes was inhibited by 33.67, 45.88 and 55.58%, respectively. OEO produced a dose-dependent effect, with linear correlation coefficient R=0.99 (y=0.0219x+23.133), and the median effective dose found was 1226.8 mg/kg. The oral administration of 1226.8 mg/kg of OEO inhibited carrageenan-induced edema by 29.18% (p<0.05) when compared to the control group. The daily administration of OEO for six days inhibited the formation of granulomatous tissue by 36.66% (p<0.01). In ear erythema induced by croton oil, OEO presented a significant inhibition (37.9%). In the vascular permeability test, treatment with OEO decreased the response to histamine, inhibiting vascular permeability by 54.16%. In carrageenan-induced peritonitis, OEO reduced the number of neutrophils migrating compared to the control group by 80.14%. These results suggested that OEO has anti-inflammatory and antinociceptive activities, probably of peripheral origin and linked to prostaglandin biosynthesis inhibition.

As atividades antiinflamatória e antinociceptiva do extrato padronizado de Hypericum brasiliense (HBSE) (Guttiferae) foi avaliada em modelos animais. Ratos Wistar machos foram tratados com extrato de H. brasiliense (50, 250 e 500 mg/kg, v.o.) em solução 3% Tween 80 0,9% NaCl. O tratamento com HBSE (500 mg/kg) mostrou inibição significativa sobre o edema induzido por carragenina comparado ao grupo controle. Nessa dose, o edema foi reduzido em 31,25% na terceira hora (pico do edema) após o tratamento, mas na dose de 50 mg/kg, o edema apresentou redução de 53,13% (p < 0,05). Ainda com a dose de 50 mg/kg, a diminuição do edema induzido por dextrana foi similar ao controle positivo, ciproeptadina. Houve diminuição na formação do tecido granulomatoso (6,6%) comparável ao grupo controle. O HBSE também inibiu o número de contorções abdominais em 46,4%, estatisticamente igual ao controle positivo, tratado com indometacina (42,9%). Na dose de 250 mg/kg, houve inibição do número de contorções em 70,7% quando comparado ao grupo controle (p < 0,001). No teste da placa-quente, foi verificado aumento no tempo de latência com a dose de 50 mg/kg. Os resultados demonstram que o HBSE possui atividade antiinflamatória sobre processos agudos, principalmente quando sua gênese está relacionada à síntese dos derivados do ácido araquidônico, e seu efeito analgésico provavelmente envolve ação sobre o Sistema Nervoso Central.

The anti-inflammatory and antinociceptive activities of the standardized leaves extract (HBSE) of Hypericum brasiliense (Guttiferae) were evaluated in animal models. Male Wistar rats were treated with H. brasiliense extract (50, 250 and 500 mg/kg, p.o.) in 3% Tween 80 0.9% saline solution. The treatment of the edema induced by carrageenin with HBSE (500 mg/kg) showed significant inhibition when compared to the control group. At this dose, the edema decreased by 31.25% in the third hour after treatment (edema peak), but the dose of 50 mg/kg has inhibited the edema by 53.13% (p < 0.05). At the dose of 50 mg/kg, the decrease of the edema induced by dextran was similar to that caused by cyproheptadine. The decrease of the formation of granulomatous tissue (6.6%) was comparable to the control group. The HBSE inhibited the abdominal constrictions induced by acetic acid. At a dose of 50 mg/kg, the inhibition of the abdominal constrictions (46.4%) was comparable to that produced by indomethacin (42.9%). A dose of 250 mg/kg inhibited these constrictions by 70.66% when compared to control (p < 0.001). In the hot-plate test, an increase in the latency time was observed at a 50 mg/kg dose. These data suggest that HBSE has anti-inflammatory activity on acute process, developed principally by arachdonic acid derivates and analgesic effect due to its probable involvement in the Central Nervous System.

Este trabalho teve como objetivo a avaliação da toxidade aguda e subaguda do óleo essencial de Piper aduncum pela determinação da DL50 em camundongos e a análise dos parâmetros bioquímicos e hematológicos em ratos. A planta é utilizada na medicina popular da região amazônica em diversas doenças e no seu óleo essencial o constituinte majoritário é o fenilpropanóide dilapiol, com propriedades inseticida, fungicida, bactericida, larvicida e moluscicida. A DL50 foi de 2,400 ± 191,7 mg/kg. O óleo essencial não alterou de maneira significativa os parâmetros hematológicos e bioquímicos em relação ao controle no tratamento subagudo, exceto a redução da creatinina. O valor da DL50 e os resultados observados nos parâmetros hematológicos e bioquímicos sugerem que o óleo essencial apresenta toxidade baixa.

The aim of this work was the acute and subacute toxicological evaluation of the essential oil of Piper aduncum with the determination of the LD50 in mice and the analysis of their hematological and biochemical parameters in rats. The plant is used in the Amazon folk medicine for several diseases and the phenylpropanoid dilapiolle is the main constituent of its essential oil, possessing insecticidal, fungicidal, bactericidal, larvicidal and molluscicidal properties. The LD50 was 2.400 ± 191.7 mg/kg. The essential oil did not change the hematological and biochemical parameters in a significant manner when compared with the control in the subacute treatment, excepting the reduction of creatinine. The LD50 and the hematological and biochemical results have suggested that the essential oil presents low toxicity.