RESUMEN
PURPOSE: To investigate the possible role of Zn as a trigger for NSF we were using a previously established preclinical model. The depletion of endogenous Zinc ions (Zn) caused by the administration of gadolinium-based contrast agents (GBCAs) has been suggested as a possible pathomechanism for nephrogenic systemic fibrosis (NSF). MATERIALS AND METHODS: In the Zn supplementation study, rats were injected with Gadodiamide, Omniscan, and Magnevist with or without Zn supplementation. In the Zn depletion study, animals were kept on a Zn-deficient diet or a special control diet and received injections of Omniscan, OptiMARK, Magnevist, Gadovist, and Gd-EDTA. Gd, Zn, and Cu concentrations in tissue were measured and histology of the skin was performed. RESULTS: As seen in earlier studies, a difference in Gd concentration in the skin was observed following treatment with the different GBCAs. High Gd concentration in the skin correlated with the occurrence of NSF-like skin lesions. We observed no differences in the occurrence of skin lesions between the Zn supplementation and the Zn-deficient groups compared to their respective control groups. CONCLUSION: We found no significant effect of Zn on the initiation of NSF-like skin lesions. The results further support data from previous studies highlighting the importance of complex stability of the investigated GBCAs.
Asunto(s)
Medios de Contraste/farmacocinética , Medios de Contraste/toxicidad , Dermopatía Fibrosante Nefrogénica/inducido químicamente , Zinc/metabolismo , Zinc/farmacología , Animales , Cobre/metabolismo , Ácido Edético/farmacocinética , Ácido Edético/toxicidad , Gadolinio DTPA/farmacocinética , Gadolinio DTPA/toxicidad , Compuestos Organometálicos/farmacocinética , Compuestos Organometálicos/toxicidad , Ratas , Ratas Wistar , Piel/metabolismoRESUMEN
We have established a rapid, homogeneous, cell-based, and highly sensitive assay for guanosine 3'-5'-cyclic monophosphate (cGMP) that is suitable for fully automated ultra-high-throughput screening. In this assay system, cGMP production is monitored in living cells via Ca2+ influx through the olfactory cyclic nucleotide-gated cation channel CNGA2, acting as the intracellular cGMP sensor. A stably transfected Chinese hamster ovary (CHO) cell line was generated recombinantly expressing soluble guanylate cyclase, CNGA2, and aequorin as a luminescence indicator for the intracellular calcium concentration. This cell line was used to screen more than 900,000 compounds in an automated ultra-high-throughput screening assay using 1536-well microtiter plates. In this way, we have been able to identify BAY 58-2667, a member of a new class of amino dicarboxylic acids that directly activate soluble guanylate cyclase. The assay system allows the real-time cGMP detection within living cells and makes it possible to screen for activators and inhibitors of enzymes involved in the nitric oxide/cGMP pathway.