RESUMO
The influence of activators (Ca(2+)-channels stimulator BAY K 8644 and phospholipase C stimulator fMLP) and inhibitors (Ca(2+)-channels blocker verapamil and alpha 1-adrenoceptors blocker prazosin) of the polyphosphoinositide system on cardiomyocytes sarcolemma, was studied. The structural effects of the PPI modifiers seem to be one of the mechanisms of the PPI physiological activity at the membrane level.
Assuntos
Coração/efeitos dos fármacos , Miocárdio/ultraestrutura , Fosfatidilinositóis/fisiologia , Sarcolema/efeitos dos fármacos , Éster Metílico do Ácido 3-Piridinacarboxílico, 1,4-Di-Hidro-2,6-Dimetil-5-Nitro-4-(2-(Trifluormetil)fenil)/farmacologia , Animais , Bovinos , Corantes Fluorescentes , Técnicas In Vitro , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Fosfatos de Fosfatidilinositol , Fosfatidilinositóis/antagonistas & inibidores , Prazosina/farmacologia , Sarcolema/ultraestrutura , Verapamil/farmacologiaRESUMO
Chloroaklylamine derivatives are studied for their effect on the structural organization of mitochondrion and microsome membranes of the cattle liver. The antitumoural preparation--embiquin is shown to increase microviscosity of hydrophobic zones of a lipid matrix of mitochondrial membranes and to decrease the quantity of immobilized cytochrome C, whereas it has no effect on microsomal membranes. It is established that the replacement of a methyl substituent in the nitrogen atom of chloroalkylamines by the metaxylyl one evokes no qualitative differences in the character of disturbances of the structural properties of mitochondrial membranes, however it induces structural perturbations in the microsomal membranes.
Assuntos
Antineoplásicos/farmacologia , Membranas Intracelulares/efeitos dos fármacos , Mecloretamina/farmacologia , Microssomos Hepáticos/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Compostos de Mostarda Nitrogenada/farmacologia , Animais , Bovinos , Grupo dos Citocromos c/metabolismo , Técnicas In Vitro , Membranas Intracelulares/enzimologia , Membranas Intracelulares/metabolismo , Lipídeos de Membrana/metabolismo , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Microssomos Hepáticos/enzimologia , Microssomos Hepáticos/metabolismo , Mitocôndrias Hepáticas/enzimologia , Mitocôndrias Hepáticas/metabolismo , Albumina Sérica/metabolismo , Espectrometria de Fluorescência , ViscosidadeRESUMO
High affinity interactions between blood serum albumin and five substances of various chemical structure, exhibiting distinct physiological activity, were accompanied by alterations in the protein tertiary structure, while the albumin secondary structure was involved in conformational transformation after less effective affinity binding.
Assuntos
Albumina Sérica , Dinitrobenzenos/farmacologia , Humanos , Ligantes , Mecloretamina/farmacologia , Organotiofosfatos/farmacologia , Compostos Organotiofosforados/farmacologia , Conformação Proteica/efeitos dos fármacos , Espectrometria de Fluorescência , Terpenos/farmacologiaRESUMO
While changing the structure of the superficial layers of the serum albumin molecule, the cholinesterase reactivator dipyroxime increases the protein binding capacity as regards the organophosphorus poison dimethyldichlorovinyl phosphate. This may be conductive to the reduction of the latter's acute toxicity.
