RESUMO
Interaction between anemone toxin BgTX8 and sodium channels in isolated single neurons of rat sensory ganglia was studied by voltage-clamp and intracellular perfusion techniques. It was shown that BgTX8 in external and internal solutions induced a dose-dependent slowdown of inactivation kinetics. Dissociation constant for receptor-toxin complex was found to be 4.10(-6) mol/l.
Assuntos
Venenos de Cnidários/farmacologia , Canais Iônicos/efeitos dos fármacos , Neurônios Aferentes/efeitos dos fármacos , Potássio/metabolismo , Animais , Venenos de Cnidários/isolamento & purificação , Relação Dose-Resposta a Droga , Interações Medicamentosas , Potenciais da Membrana/efeitos dos fármacos , Ratos , Sódio/metabolismoRESUMO
The intracellular distribution of 67Ga was studied in solid hepatoma 22 implanted in C3Ha/6 mice and in normal liver tissue from the same animals at different time intervals. The tissues were fractionated according to differential centrifugation principles, and subcellular fractions were isolated consecutively. The enzyme activities and the accumulation of 67Ga were determined in each fraction. The subcellular distribution of 67Ga in the tumor tissue was different compared with normal liver; in tumor it was found mainly in the nuclear fraction and this distribution was independent of time, but in normal liver the accumulation was mainly in the mitochondrial fraction, this was time-dependent and the maximal uptake was found 48 h after 67Ga administration.
Assuntos
Radioisótopos de Gálio/metabolismo , Neoplasias Hepáticas Experimentais/metabolismo , Fosfatase Ácida/metabolismo , Animais , Catepsina D , Catepsinas/metabolismo , Núcleo Celular/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Glucose-6-Fosfatase/metabolismo , Fígado/metabolismo , Lisossomos/metabolismo , Camundongos , Camundongos Endogâmicos C3H , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/metabolismo , NADH Desidrogenase/metabolismo , Succinato Desidrogenase/metabolismoRESUMO
A compound was synthetized, which by X-Ray diffraction studies proved to be hexahydrated sodium tripolyphosphate. By means of in vitro procedures, it was demonstrated that this compound was able to complex trivalent cations, and that 113mIn could be completely incorporated to it. In vivo studies in rats, and scans performed with this new radiopharmaceutical in humans showed its highly selective accumulation in metastasic bone tumors.
