中文摘要：

The myosin light chain 2 promoter-human heart chymase (MLC2-hChymase) transgenic mice founded by our laboratory were used as the model to study the function of chymase in the heart angiotension Ⅱ (Ang Ⅱ) formation and heart remodeling. Tissue-specific expression of human heart chymase gene and transcriptional expression of type Ⅰ and type Ⅲ collagens genes were analyzed by RT-PCR. Activities of chymase, ACE and the levels of Ang Ⅱ in heart and plasma were determined with radioimmunoas-say (RIA) kit. Activity of heart matrix metalloproteinase-9 (MMP-9) was detected using gelatin zymography. The cardiac hypertrophic phenotypes were also observed with the physiological and morphological methods. The results in the MLC2-hChymase transgenic mice indicated: ( i ) human heart chymase gene was expressed specially in the heart; (u) heart chymase activity increased markedly in the transgenic mice vs non-transgenic mice (control) (0.27±0.07 U/mg vs. 0.15±0.02 U/mg, P【0.05) with no significant difference in A