RESUMO
Erythrocyte membrane potential was recorded via measurement of pH of the incubation medium in presence ofprothonophore. The increase of intracellular calcium concentration in presence of calcium ionophore A23187 and addition of the artificial redox-system ascorbate-phenazine methosulfate led to membrane hyperpolarization due to opening of Ca(2+)-activated potassium channels that are regulated by multiple signaling pathways. The opening of the Ca(2+)-activated potassium channels in presence of artificial redox-system ascorbate-phenazine methosulfate is mediated at least by two mechanisms including an increase in affinity of channels to calcium ions and involvement of the protein SH-groups and the components of the respiratory circuit which have beer found in erythrocyte membrane.
Assuntos
Ácido Ascórbico/metabolismo , Membrana Eritrocítica/metabolismo , Metilfenazônio Metossulfato/metabolismo , Canais de Potássio Cálcio-Ativados/metabolismo , Calcimicina/farmacologia , Humanos , Ionóforos/farmacologia , Potenciais da Membrana/efeitos dos fármacosRESUMO
Increase in intracellular Ca2+ concentration caused by calcium ionophore A23187 or ascorbate+phenazine methosulphate electron donor system added to erythrocyte suspension induced similar shifts in erythrocyte membrane potential. These processes are most likely mediated by Ca2+-activated potassium channels. Changes in the osmolarity of the incubation medium produced opposite effects on membrane hyperpolarization induced by A23187 or ascorbate+phenazine methosulphate in erythrocyte isolated from healthy donors, which attests to the existence of different mechanisms of regulation of Ca2+-activated potassium channels. There was no difference in the volume-dependent changes of potassium permeability in cells from patients with type II diabetes mellitus combined with arterial hypertension induced by application A23187 or electron-donor system.
Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Eritrócitos/fisiologia , Hipertensão/complicações , Canais de Potássio Cálcio-Ativados/fisiologia , Calcimicina/farmacologia , Diabetes Mellitus Tipo 2/complicações , Membrana Eritrocítica/efeitos dos fármacos , Humanos , Potenciais da Membrana/efeitos dos fármacos , Concentração OsmolarRESUMO
A case of systemic lupus erythematosus (SLE) in a 37-year-old female is described which was primarily diagnosed as epilepsy. Immunopathologically, an immunoglobulin in the nuclei of the majority of cells in the skin biopsy and blood cells was found against the background of the lack of SLE manifestations (antinuclear factor in the circulating blood, skin lesions, etc.). Antibodies against the antigen of vascular intima are revealed in the blood by means of the indirect immunofluorescence. The epilepsy diagnosis was established due to the prevalence of the brain vessels affection (frequent loss of consciousness). The progression of the disease with the involvement of joints, heart, lungs and other organs, high indexes of the rheumatoid factor made it necessary to differentiate between rheumatoid arthritis and SLE. The immunopathological examination confirmed the SLE diagnosis. Hemosorption combined with a standard therapy was followed by the decrease of the immunopathological manifestations.
Assuntos
Lúpus Eritematoso Sistêmico/diagnóstico , Adulto , Biópsia , Diagnóstico Diferencial , Epilepsia/diagnóstico , Feminino , Imunofluorescência , Humanos , Imunoglobulina G/análise , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Pele/imunologia , Pele/patologiaRESUMO
Analysis of the characteristic changes in the activity of the tetrade of lymphocyte dehydrogenases (malate, lactate, succinate and mitochondrial alpha-glycerophosphate dehydrogenase) in patients suffering from chronic lymphoid leukemia is regarded by the authors of the paper as one of the sources of information permitting one to forecast the course of the disease under study.