RESUMO
Changes in the activity of ß2-adrenergic receptors of human T-lymphocytes under the effect of salbutamol (a short-acting ß2-agonist) have been evaluated with a new modified radioligand method utilizing [^(125)I]cyanopindolol and a specific ligand ICI 118551. In healthy volunteers, the receptor activity decreased after 30 min upon the inhalation of salbutamol and restored to the initial level after 2 h. At the same time, there were changes in the transcription level of the ADRB2 gene, which encodes the protein component of the ß2-adrenoreceptor. The dynamics of ß2-adrenergic receptor activity of T-lymphocytes after salbutamol treatment in patients with cardiorespiratory pathology significantly differed from that in healthy volunteers.
Assuntos
Agonistas de Receptores Adrenérgicos beta 2/administração & dosagem , Albuterol/administração & dosagem , Receptores Adrenérgicos beta 2/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/metabolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Masculino , Pessoa de Meia-Idade , Doenças Respiratórias/tratamento farmacológico , Doenças Respiratórias/metabolismoRESUMO
We proposed a new method of evaluation of beta-receptor's activity on the surface of human T-lymphocytes based on the radioligand method. Optimal conditions for evaluation of specific binding to ß2-adrenoceptors of 0.5 fmol ligand per 1 million cells using [125I]-cyanopindolol were found. The possibility of using of ß2-adrenoceptor's activity assessment in clinical settings was demonstrated on human T-lymphocyte.
Assuntos
Antagonistas Adrenérgicos beta , Pindolol/análogos & derivados , Receptores Adrenérgicos beta/metabolismo , Linfócitos T/metabolismo , Células Cultivadas , Humanos , Radioisótopos do Iodo , Ligantes , Ligação Proteica , Ensaio RadioliganteRESUMO
New gamma-substituted analogues of dNTP were synthesized and their enzymatic stability and antiviral properties were evaluated.
Assuntos
Fármacos Anti-HIV/síntese química , Fármacos Anti-HIV/farmacologia , Fosfatos de Dinucleosídeos/síntese química , Fosfatos de Dinucleosídeos/farmacologia , Inibidores da Transcriptase Reversa/síntese química , Inibidores da Transcriptase Reversa/farmacologia , Animais , Fármacos Anti-HIV/sangue , Fosfatos de Dinucleosídeos/sangue , Estabilidade de Medicamentos , Fibroblastos/virologia , HIV/efeitos dos fármacos , HIV/enzimologia , Humanos , Vírus da Leucemia Murina de Moloney/efeitos dos fármacos , Vírus da Leucemia Murina de Moloney/enzimologia , Ratos , Inibidores da Transcriptase Reversa/sangueRESUMO
A method is proposed for localization of the sites of affinity labelling of the beta subunit of Escherichia coli RNA polymerase. The principle of this method is similar to that of the methods of rapid sequencing of nucleic acids. The polypeptide bearing a radioactive affinity label at one of the amino acid residues is subjected to short-term treatment with cyanogen bromide. The conditions of this reaction are selected in such a way that less than one cleavage occurs on average per polypeptide chain. Two series of radioactive peptides are formed, one involving all the possible N-terminal peptides and the other the C-terminal peptides. The distribution of the lengths of these peptides is studied by means of gel electrophoresis and compared with the theoretical ones based on the known amino acid sequence of the beta subunit. Obviously, the affinity label resides between the C-terminus of the shortest N-terminal radioactive peptide and the N-terminus of the shortest C-terminal radioactive peptide. In order to increase reliability and resolution of the method, partial trypsinolysis may be employed. The evidence obtained suggests that lysine residues over the regions 1036-1066, 1234-1242, and histidine-1237 are situated in the nearest neighbourhood to, or directly involved in the formation of the active center of initiating substrate binding of the beta subunit of E. coli RNA polymerase.
