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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Activation of TP receptors induces high release of PGI(2) in coronary arteries of renal hypertensive rats

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Paula, T. D. [1] ; Silva, B. R. [1] ; Grando, M. D. [1] ; Souza, H. C. D. [2] ; Bendhack, L. M. [1]
Total Authors: 5
[1] Univ Sao Paulo, Fac Pharmaceut Sci Ribeirao Preto, Dept Phys & Chem, Ribeirao Preto, SP - Brazil
[2] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Physiol, Ribeirao Preto, SP - Brazil
Total Affiliations: 2
Document type: Journal article
Web of Science Citations: 1

Aim: To investigate the molecular mechanisms and cellular signaling pathways involved in the activation of TP receptors and the consequent induction of contractile responses in coronary arteries of renal hypertensive (2K-1C) rats. Methods and results: The coronary perfusion pressure (CPP) was lower in 2K-1C rats during increased coronary flow as measured by the Langendorff technique. The coronary contraction and relaxation were evaluated by vascular reactivity studies, and the molecular mechanisms were investigated on the basis of the protein expression of TP receptors, Cav-1, eNOS, COX-1, and COX-2, as measured by Western blot. The levels of eicosanoids were determined by ELISA immunoassay and analyzed by reverse-phase HPLC coupled to electrospray ionization mass spectrometry (HPLC-MS/MS). The metabolites from NO production were evaluated by the Griess reaction. The coronary arteries of 2K-1C rats expressed COX-2 to a larger extent and TP receptors to a lesser extent than the coronary arteries of normotensive (2K) rats. Selective COX-1 and non-selective COX inhibitors reversed the reduction in the contraction induced by TP receptors in the coronary arteries of 2K-1C rats. U46619, an agonist of TP receptors, induced a contractile response that was relaxed by acetylcholine (ACh). In the coronary arteries of 2K-1C rats, this ACh-induced relaxation depended on COX. The activation of TP receptors increased the production of PGI(2) in the coronary arteries of 2K-1C rats. The results demonstrated that increased COX signaling in the coronary arteries of 2K-1C rats mediated the low levels of CPP, the contraction induced by the activation of TP receptors, and the endothelium-dependent relaxation. The vasodilator PGI(2) seemed to be the major product. Conclusion: Activation of TP receptors increases production of PGI(2) in coronary arteries of 2K-1C rats. (AU)

FAPESP's process: 15/17080-2 - Effects of the stretching on the vasoconstriction modulated by the endothelium in renal hypertensive rat aorta and coronary arteries
Grantee:Lusiane Maria Bendhack
Support type: Regular Research Grants
FAPESP's process: 15/00658-1 - New functional aspects of eicosanoids
Grantee:Lúcia Helena Faccioli
Support type: Multi-user Equipment Program