RESUMO
This work describes a cell-based assay that does not depend on radioactivity or laboratory animals for the detection of ligands of angiotensin II type 1 receptor (AT1R). The assay makes use of stable transfected Chinese hamster ovary cells (CHO-AT1R) expressing the AT1R. A sequential saturation assay principle was used in which receptor binding sites of the CHO-AT1R cells are blocked by the analyte in a concentration-dependent manner. Afterwards, TAMRA-angiotensin II, a fluorescence-labeled ligand, was added to bind to the remaining free binding sites of the receptor. In consequence, the fluorescence signal determined is inversely proportional to the concentration of the analyte.
Assuntos
Angiotensina II/química , Técnicas Citológicas , Medições Luminescentes/métodos , Receptor Tipo 1 de Angiotensina/química , Angiotensina II/metabolismo , Animais , Sítios de Ligação , Células CHO , Cricetinae , Cricetulus , Cinética , Ligantes , Ligação Proteica , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismoRESUMO
The synthesis of spacer-linked neoaminoglycoside 5 is described. Key steps of the synthesis are the introduction of nitrogen functionalities at C-3 and C-6 and the olefin cross metathesis of allyl glycoside 16. Although it is known that Grubbs catalysts tolerate nitrogen functionalities, difficulties were encountered in the cross metathesis reaction. Factors that govern this dimerization are the steric and electronic demands of the catalyst and the substrate. Preliminary biological evaluation of homodimer 5, by studying the inhibition of HIV-1 TAR-RNA/Tat-peptide complex using a method based on fluorescence titration, revealed an inhibitory effect of 5.