JEREZ Susana Josefina
congresos y reuniones científicas
Incremento en la reactividad vascular a angiotensina II inducida por una dieta rica en colesterol: papel de los metabolitos de la omega hidroxilasa.
JEREZ S; SIERRA L; GUERRERO R; PERAL DE BRUNO M
Tucumán, Tafi del Valle
Jornada; XXIII Jornadas Científicas de la Sociedad de Biología de Tucumán; 2006
Sociedad de Biología de Tucumán
INCREASED VASCULAR REACTIVITY TO ANGIOTENSIN II INDUCED BY HIGH CHOLESTEROL DIET: ROLE OF OMEGA HYDROXYLASE METABOLITES. Jerez S., Sierra L. and Peral de Bruno M. UNT-INSIBIO-CONICET. firstname.lastname@example.org The aim of this work was to study the role of the omega hydroxylase metabolites on the vascular reactivity to angiotensin II (Ang II) in hypercholesterolemic rabbits. Rabbits were feed with either normal rabbit chow (CD) or a diet cointaining 1% cholesterol for 6 weeks (HD). PAM, CT, LDL, HDL and TG were measured. Thoracic aorta was excised. Rings were cut and mounted in a organ bath to register isometric contractions in arteries with (E+) or whithout (E-) endothelium. One cumulative dose response curve (CDRC) to Ang II was performed. 17-ODYA 10-6 M (omega hydroxylase inhibitor) and/or indomethacin 10-5 M (cycloxygenase inhibitor) was added 30 min. before the CDRC to Ang II. Results: CT and LDL were higher in HD. HD improves Ang II- response in E+ and there was differences between E+ and E-. This effect was blocked by 17-ODYA and indomethacin. However, in CD, 17-ODYA increased Ang II-response both in E+ and E-. Indomethacin was able to inhibit this phenomenon. Conclusions: hypercholesterolemia would increase 20-HETE production. This omega hydroxylase metabolite would be metabolized by cyclooxygenase to vasoconstrictor endoperoxides that improve Ang II-contractile response. In physiological state, such metabolites would inhibit cyclooxygenase to maintain vascular homeostasis.