(Hypertension. 1999;34:914-919.)
© 1999 American Heart Association, Inc.
Scientific Contributions |
From the Laboratory of Hypertension, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, Brazil.
Correspondence to Maria Helena C. Carvalho, Laboratory of Hypertension, Department of Pharmacology, Institute of Biomedical Science, University of São Paulo, 05508-900, Av Prof Lineu Prestes, 1524, São Paulo, SP, Brazil. E-mail mahecaca{at}.icb.usp.br
AbstractAlthough female sex
hormones may attenuate endothelial dysfunction in
spontaneously hypertensive rats (SHR) by increasing
endothelium-derived relaxing factors (EDRFs), the
influence of ovarian hormones on the generation of
endothelium-derived contracting factors (EDCFs) remains
unknown. The aim of this study was to evaluate the effect of estrogen
and progesterone on the generation of vasoconstrictor prostanoids and
superoxide anion (O2-) by microvessels from
SHR. Vascular reactivity to norepinephrine (NE),
acetylcholine (ACh), and sodium nitroprusside (SNP) were evaluated in
the mesenteric arteriolar bed from estrous (OE) and ovariectomized
(OVX) SHR. OVX-SHR were treated for 24 hours or 15 days with estradiol
and for 15 days with estradiol+progesterone. The vascular reactivity
was evaluated in the absence or presence of
indomethacin (INDO, 10 µmol/L) and sodium
diclofenac (DIC, 10 µmol/L), ridogrel (RID, 50 µmol/L),
dazoxiben (DAZ, 10 µmol/L), or superoxide dismutase (SOD, 100
U/mL). Prostanoid levels in the arteriolar perfusate of
mesenteries with or without endothelium were measured
by enzyme immunoassay. An increased reactivity to NE and reduced
sensitivity to ACh were observed in microvessels from OVX-SHR compared
with OE-SHR. There were no differences in the responses to SNP.
Treatments with estradiol and estradiol+progesterone similarly restored
these altered responses. INDO, DIC, RID, and SOD also restored the NE
and ACh responses in OVX-SHR. DAZ had no effect on the vascular
reactivities. The release of PGF2
, but not of
TXB2 and 6-keto-PGF1
, was greater in OVX-SHR
than in OE-SHR microvessels with endothelium when
stimulated by NE. This response was normalized by hormonal treatments.
Neither NE nor ACh stimulated prostanoid production by
microvessels without endothelium. These results suggest
that estrogen may protect female SHR against severe hypertension partly
by decreasing the synthesis of EDCFs such as
PGH2/PGF2
and O2-.
Key Words: estrogen progesterone SHR endothelium-derived contracting factors prostanoids superoxide
This article has been cited by other articles:
![]() |
M. P. Kunert, M. R. Dwinell, I. Drenjancevic Peric, and J. H. Lombard Sex-specific differences in chromosome-dependent regulation of vascular reactivity in female consomic rat strains from a SS x BN cross Am J Physiol Regulatory Integrative Comp Physiol, August 1, 2008; 295(2): R516 - R527. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Lopez-Sepulveda, R. Jimenez, M. Romero, M. J. Zarzuelo, M. Sanchez, M. Gomez-Guzman, F. Vargas, F. O'Valle, A. Zarzuelo, F. Perez-Vizcaino, et al. Wine Polyphenols Improve Endothelial Function in Large Vessels of Female Spontaneously Hypertensive Rats Hypertension, April 1, 2008; 51(4): 1088 - 1095. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. L. de Oliveira, H. V. Domingos, G. Cavriani, A. S. Damazo, A. L. dos Santos Franco, S. M. Oliani, R. M. Oliveira-Filho, B. B. Vargaftig, and W. T. de Lima Cellular recruitment and cytokine generation in a rat model of allergic lung inflammation are differentially modulated by progesterone and estradiol Am J Physiol Cell Physiol, September 1, 2007; 293(3): C1120 - C1128. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. V. Landgraf, L. L. Martinez, V. M. F. Rastelli, M. d. C. P. Franco, M. Soto-Suazo, R. d. C. A. Tostes, M. H. C. Carvalho, D. Nigro, and Z. B. Fortes Intrauterine Undernutrition in Rats Interferes with Leukocyte Migration, Decreasing Adhesion Molecule Expression in Leukocytes and Endothelial Cells J. Nutr., June 1, 2005; 135(6): 1480 - 1485. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Widder, T. Pelzer, C. von Poser-Klein, K. Hu, V. Jazbutyte, K.-H. Fritzemeier, C. Hegele-Hartung, L. Neyses, and J. Bauersachs Improvement of Endothelial Dysfunction by Selective Estrogen Receptor-{alpha} Stimulation in Ovariectomized SHR Hypertension, November 1, 2003; 42(5): 991 - 996. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. J. Armstrong, Y. Zhang, K. G. Stewart, and S. T. Davidge Estrogen replacement reduces PGHS-2-dependent vasoconstriction in the aged rat Am J Physiol Heart Circ Physiol, September 1, 2002; 283(3): H893 - H898. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. P. V. Dantas, R. C.A. Tostes, Z. B. Fortes, S. G. Costa, D. Nigro, and M. H. C. Carvalho In Vivo Evidence for Antioxidant Potential of Estrogen in Microvessels of Female Spontaneously Hypertensive Rats Hypertension, February 1, 2002; 39(2): 405 - 411. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. L. David, M. H. C. Carvalho, A. L.N. Cobra, D. Nigro, Z. B. Fortes, N. A. Reboucas, and R. C.A. Tostes Ovarian Hormones Modulate Endothelin-1 Vascular Reactivity and mRNA Expression in DOCA-Salt Hypertensive Rats Hypertension, September 1, 2001; 38(3): 692 - 696. [Abstract] [Full Text] [PDF] |
||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1999 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |