RESUMEN
The effects of oral supplementation of chromium picolinate (CrPic) on humoral and cellular immunity in sheep were investigated. Twenty-four male lambs divided into four treatments and received different dosages of CrPic: placebo (0), 0.250, 0.375, and 0.500 mg of chromium/animal/day during 84 days. The base ration was Panicum maximum cv Massai hay and concentrate. Blood samples were collected fortnightly for total and differential leukocyte counts. On days 28 and 56, the lambs were challenged with chicken ovalbumin I.M. Serum samples were collected on days 46 and 74 and subjected to an indirect enzyme-linked immunosorbent assay to measure IgG anti-ovalbumin. The cell-mediated immune response was determined by a delay-type hypersensitivity test using phytohemagglutinin. CrPic did not significantly affect humoral immunity in lambs but there was a negative effect on cellular immunity (P < 0.05) as Cr supplementation increased. Therefore, the level of Cr supplementation for lambs must be better studied to address its effect on stressed animals or the possible toxic effects of Cr on the animal itself or its immune system.
Asunto(s)
Suplementos Dietéticos , Inmunidad Celular/efectos de los fármacos , Inmunidad Humoral/efectos de los fármacos , Quelantes del Hierro/farmacología , Ácidos Picolínicos/farmacología , Animales , Hipersensibilidad Tardía/sangre , Hipersensibilidad Tardía/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Masculino , OvinosRESUMEN
Leaves of Maytenus species are commonly used in Brazil for the treatment of gastric ulcers, dyspepsias and other gastric problems. The present study evaluated the antiulcerogenic potential of a boiling water extract of equal parts of M. aquifolium and M. ilicifolia leaves against ulcer lesions induced by indomethacin and cold-restraint stress in rats. Ranitidine and cimetidine were used as reference drugs. The oral and intraperitoneal administration of the extract had a potent antiulcerogenic effect against both types of ulcers. The extract was shown to cause an increase in volume and pH of gastric juice of the animals with the pH effects comparable to those of cimetidine. The results tend to confirm the popular use of the plant.
Asunto(s)
Antiulcerosos/farmacología , Plantas Medicinales/química , Úlcera Gástrica/prevención & control , Administración Oral , Animales , Antiulcerosos/análisis , Brasil , Cimetidina/uso terapéutico , Frío , Ácido Gástrico/metabolismo , Indometacina/toxicidad , Inyecciones Intraperitoneales , Masculino , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Ratas , Ratas Endogámicas , Restricción Física , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/etiologíaRESUMEN
Cinco diferentes amostras de Maytenus sp (espinheira-santa), três delas a M. ilicifolia e duas a M. aquifolium revelaram potente efeito antiúlcera gástrica, quando utilizadas, por via i.p., sob a forma de liofilizados, obtidos a partir de abafados, em ratos submetidos aos processos de induçäo de úlcera por endometacina ou por stress de imobilizaçäo em baixa temperatura. O efeito portetor é dose-dependente, persiste no mínimo até 16 meses após a coleta da planta e é equiparável aos efeitos da cimetidina e ranitidina. Além da atividade antiúlcera, o liofilizado a espinheira-santa, a semelhança da cimetidina, aumentou grandemente o volume e o pH do conteúdo gástrico. Foi discutido se o efeito obtido com o liofilizado da espinheira-santa poderia ser devido a derivados tanínicos presentes no mesmo