Angiotensin II induces TIMP-1 production in rat heart endothelial cells
Angiotensin II (All) was found to upregulate tissue inhibitor of metalloproteineses-1 (TIMP-1) gene expression in rat heart endothelial cells in a dose and time-dependent manner. The maximal stimulation of TIMP-1 mRNA was achieved by 2 h after the addition of All. This effect was blocked by losartan, an AT1 receptor antagonist and by calphostin C, a protein kinase C inhibitor. Addition of cycloheximide superinduced and actinomycin D abolished the induction. These results suggest that All stimulates TIMP-1 production by a protein kinase C dependent pathway which is dependent upon de novo RNA synthesis. Immunoprecipitation experiment showed an enhanced band of 28 kDa from the conditioned medium of All-treated cultures. Immunoblot analysis revealed that TIMP-1 was detectable in the conditioned medium 4 h after All stimulation. Since endothelial cells line the blood vessels and sense the rise in All associated with hypertension, the TIMP-1 released by these cells may provide an initial trigger leading to cardiac fibrosis in angiotensin-renin dependent hypertension.
Chua, Chu Chang; Hamdy, Ronald C.; and Chua, Balvin H.L.. 1996. Angiotensin II induces TIMP-1 production in rat heart endothelial cells. Biochimica et Biophysica Acta - Molecular Cell Research. Vol.1311(2). 175-180. https://doi.org/10.1016/0167-4889(95)00205-7 PMID: 8664344 ISSN: 0167-4889