RESUMO
Peptide self-assembled multilayers ( SAMs ) was coated onto the quartz surface. The assembly conditions, such as the assembly agent concentration and assembly time, were examined. The SAMs was characterized via UV-vis absorption spectrometry and scanning electron microscope. Our results showed that the optimal concentration and assembly time for the 3-aminopropyl-triethoxysilane aqueous were 1% ( V/V ) and 3 h respectively, and those of gold nanoparticles were 2. 4 × 10-4 mol/L and 12 h, respectively, while those of peptide solution were 1 × 10-4 mol/L and 12 h, respectively. A new sensitive method, based on the theory that peptide could be cleaved at the site of Arg-Gly by thrombin, was established to detect thrombin. In addition, a good linear relationship was obtained in the range from 2. 8×10-12 mol/L to 9. 9×10-10 mol/L, and the detection limit was 1. 4×10-12 mol/L. The peptide self-assembled multilayers were also used in the analysis of blood serum samples, and the recovery rate was within the range from 91. 6% to 107. 6%.
RESUMO
Aim To investigate the change in neuropeptide Y(NPY) Y1 receptor level in infarcted myocardium tissues of (MI) rats. Method MI was induced by ligating the left descending anterior coronary artery (LAD) in the heart of rats. The techniques of reverse transcription polymerase chain reaction (RT-PCR) were used to identify the exist of NPY Y1 receptor mRNA in myocardial tissues. The technique of semi-quantitative PCR wa s used to observe the change of NPY Y1 receptor mRNA level. Results NPY Y1 receptor mRNA distributed in the heart tissues of rat. Compared with sham operated rats ,the NPY Y1 receptor mRNA level both in infarction area and non-infarction area was increased significantly after MI fo r 1d and 3d. The NPY Y1 receptor mRNA level in the heart tissues of sham-op erated rats was also significantly increased compared with that in control rats . Conclusion These results suggest that MI may result in increase NPY Y1 receptor level in the heart tissues of rats. Stre ss stimulation such as surgery may also increase the NPY Y1 receptor level in the heart.