RESUMO
1. The activity of the rat liver monooxygenase system after single and combined treatment with Fasciola hepatica and diethylnitrosamine (DENA) has been studied in a 27-week experiment. 2. The changes in lever drug metabolism were due mainly to F. hepatica with DENA having a modulating effect only. 3. The results are discussed with reference to earlier data of ours concerning the effects of stimulation or inhibition of DENA-induced liver carcinogenesis against a background of acute or chronic fascioliasis.
Assuntos
Carcinógenos/toxicidade , Dietilnitrosamina/toxicidade , Fasciolíase/enzimologia , Fígado/enzimologia , Oxigenases de Função Mista/metabolismo , Animais , Fígado/efeitos dos fármacos , Masculino , Oxigenases de Função Mista/efeitos dos fármacos , Ratos , Ratos EndogâmicosRESUMO
Bangham-type liposomes, undergoing freeze-thawing cycles, were detected electron microscopically in the brain, liver and spleen of experimental animals 24 h after rectal administration. This novel approach has several important advantages over intravenous, intraperitoneal and other usual means of administration of liposome drug-entrapped treatment and diagnostics for human application. The location of the liposomes in the brain after rectal administration shows that the brain-blood barrier can be overcome successfully by this method. Moreover, the risk of embolism and hypersensitivity, strict control of sterility and some other undesirable effects can be avoided. The possible role of rectal administration in the development of liposome drug-entrapped treatment and diagnostics is discussed.
Assuntos
Encéfalo/metabolismo , Lipossomos/metabolismo , Fígado/metabolismo , Baço/metabolismo , Administração Retal , Animais , Feminino , Masculino , Camundongos , RatosRESUMO
Male Wistar rats were treated by 9 i.p. injections with 100 mg/kg body weight diethylnitrosamine (DEN), in 9 consecutive weeks. After decapitation, between the 130th and 140th day, primary hepatocellular carcinomas were found. Tissue from 3 different parts of the liver was processed to study the activity of Glucose-6-Phosphatase in the membranes of the endoplasmic reticulum, Adenosinetriphosphatase in the cell (plasma) membrane and of Succinic-Dehydrogenase in mitochondrial membranes. In the experimental animals liver tissue revealed no activity of G-6-P in any region affected by the tumor. ATP and SDG activity was dependent on the type of lesion. Generally speaking it diminished with the lesser differentiation of the hepatoma cells. Other morphological and metabolic aspects of liver DEN cancerogenesis are discussed.
