(Hypertension. 2000;36:642.)
© 2000 American Heart Association, Inc.
Colin Johnston - A Celebration |
From the Department of Nephrology (L.G.S.-L., A.B., F.J., J.H.-A., N.A.B.), Instituto Nacional de Cardiología Ignacio Chávez; and the Molecular Physiology Unit (G.G.), Instituto de Investigaciones Biomédicas, UNAM and Instituto Nacional de la Nutrición Salvador Zubirán, Mexico City, Mexico.
Correspondence to Norma A. Bobadilla, PhD, Department of Nephrology, Instituto Nacional de Cardiología I.Ch., Juan Badiano No 1, Col Sección XVI, Mexico City, Mexico, CP 14080. E-mail nbobadillas{at}mailer.main.conacyt.mx
AbstractCyclosporine toxicity mainly affects kidney and liver function. We have previously shown that cyclosporine nephrotoxicity alters kidney nitric oxide synthase mRNA pattern of expression. To determine if nitric oxide synthase expression changes are mediated directly by cyclosporine or by secondary hemodynamic alterations induced by cyclosporine, we evaluated if these effects are tissue specific and if nifedipine-induced vasodilation prevents these alterations. Uninephrectomized Wistar rats treated for 7 days with olive oil, cyclosporine (30 mg/kg), nifedipine (3 mg/kg), and nifedipine+cyclosporine were studied. In vehicle and cyclosporine groups, the gene expression of the neuronal, inducible, and endothelial nitric oxide synthases in cerebellum, heart, intestine, liver, renal cortex, and medulla was evaluated. The administration of cyclosporine was associated with nephrotoxicity and hepatotoxicity, increased endothelial nitric oxide synthase mRNA levels in renal cortex and liver, and a decrease in inducible nitric oxide synthase and neuronal nitric oxide synthase in renal medulla. The mRNA levels of the 3 nitric oxide synthase isoforms were not affected in any other tissue. Nifedipine did not alter nitric oxide synthase expression in the control group but prevented changes associated with cyclosporine. These results suggest that cyclosporine-induced changes in the pattern of expression of the nitric oxide synthases may be secondary to its hemodynamic effects.
Key Words: nitric oxide liver hypertension cyclosporine
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2000 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |