RESUMEN
BACKGROUND: Stem cell transplantation has been shown to have beneficial effects on dilated cardiomyopathy. However, mechanism for stem cell homing to cardiac tissue in dilated cardiomyopathy has not yet been elucidated. METHODS: Mesenchymal stem cells were obtained from rat bone marrow, expanded in vitro, and labeled with (99m)Tc. Cardiomyopathy model was induced by doxorubicin in rats. (99m)Tc labeled cells were infused into the left ventricles in cardiomyopathy and control rats. Sixteen hours after injection, animals were sacrificed and different tissues were harvested to measure specific radioactivity. By use of real-time polymerase chain reaction and immunohistochemistry, mRNA and protein expressions for stromal-cell-derived factor 1 in cardiac tissue were measured. RESULTS: Labeling efficiency of mesenchymal stem cells was (70.0 ± 11.2)%. Sixteen hours after mesenchymal stem cell transplantation, the heart-to-muscle radioactivity ratio was increased significantly in cardiomyopathy hearts as compared to control hearts. Both mRNA and protein expressions of stromal-cell-derived factor 1 were up-regulated in cardiomyopathy hearts as compared with control hearts. CONCLUSION: In dilated cardiomyopathy induced by doxorubicin up-regulated expression of stromal-cell-derived factor 1 in heart may induce mesenchymal stem cells home to the heart.
Asunto(s)
Células de la Médula Ósea/citología , Cardiomiopatía Dilatada/terapia , Quimiocina CXCL12/metabolismo , Células Madre Mesenquimatosas/citología , Animales , Células de la Médula Ósea/metabolismo , Células Cultivadas , Quimiocina CXCL12/genética , Inmunohistoquímica , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
To develop a rapid, simple and sensitive method for determining the concentration of tetrodotoxin(TTX), TTX was hydrolyzed in the strong alkali solution of water mixed with isopropanol. The concentration of TTX can be indirectly analyzed by the fluorescence signal of its alkaline hydrolysis product which can be enhanced by the microwave method. The maximum excitation and emission wavelengths of the alkaline hydrolysis product of tetrodotoxin were 380 and 496 nm, respectively. The linear range of the calibration curve was 0. 1-10 micromol x L(-1) with r=0. 9991. The limit of detection was 0. 05 micromol x L(-1) , which was twenty times lower than before. A rapid, highly sensitive and accurate method was thus established. It can be used as a quantitative method for detecting TTX.
