Nitric oxide regulates angiotensin-I converting enzyme under static conditions but not under shear stress
AUTOR(ES)
Pertrini, C.M., Miyakawa, A.A., Laurindo, F.R.M., Krieger, J.E.
FONTE
Brazilian Journal of Medical and Biological Research
DATA DE PUBLICAÇÃO
2003-09
RESUMO
Mechanical forces including pressure and shear stress play an important role in vascular homeostasis via the control of the production and release of a variety of vasoactive factors. An increase in vascular shear stress is accompanied by nitric oxide (NO) release and NO synthase activation. Previously, we have demonstrated that shear stress induces angiotensin-I converting enzyme (ACE) down-regulation in vivo and in vitro. In the present study, we determined whether NO participates in the shear stress-induced ACE suppression response. Rabbit aortic endothelial cells were evaluated using the NO synthase inhibitor L-NAME, and two NO donors, diethylamine NONOate (DEA/NO) and sodium nitroprusside (SNP). Under static conditions, incubation of endothelial cells with 1 mM L-NAME for 18 h increased ACE activity by 27% (from 1.000 ± 0.090 to 1.272 ± 0.182) while DEA/NO and SNP (0.1, 0.5 and 1 mM) caused no change in ACE activity. Interestingly, ACE activity was down-regulated similarly in the presence or absence of L-NAME (delta(0 mM) = 0.26 ± 0.055, delta(0.1 mM) = 0.21 ± 0.22, delta(1 mM) = 0.36 ± 0.13) upon 18 h shear stress activation (from static to 15 dyn/cm²). Taken together, these results indicate that NO can participate in the maintenance of basal ACE levels in the static condition but NO is not associated with the shear stress-induced inactivation of ACE.
Documentos Relacionados
- The angiotensin-I converting enzyme (ACE) gene I/D polymorphism and ACE levels in Pima Indians.
- Increased angiotensin-I converting enzyme gene expression in the failing human heart. Quantification by competitive RNA polymerase chain reaction.
- Constitutive production of angiotensin converting enzyme from rheumatoid nodule cells under serum free conditions.
- Angiotensin-I-converting enzyme and its relatives
- Role of angiotensin-I converting enzyme in the regulation of the hematopoietic response normal and kinin receptor B1 kockout mice.