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Early gestation dexamethasone programs enhanced postnatal ovine coronary artery vascular reactivity. Am J Physiol Regul Integr Comp Physiol 2005 Jan;288(1):R46-53

Date

06/26/2004

Pubmed ID

15217789

DOI

10.1152/ajpregu.00165.2004

Scopus ID

2-s2.0-11144254396   32 Citations

Abstract

Excessive exposure of the fetus to maternally derived corticosteroids has been linked to the development of adult-onset diseases. To determine if early gestation corticosteroid exposure alters subsequent coronary artery reactivity, we administered dexamethasone (0.28 mg.kg(-1).day(-1)) to pregnant ewes at 27-28 days gestation (term being 145 days). Vascular responsiveness was assessed in endothelium-intact coronary and mesenteric arteries isolated from steroid-exposed and age-matched control fetal sheep at 123-126 days gestation and lambs at 4 mo of age. Lambs exposed to maternal dexamethasone had higher mean arterial blood pressures than the age-matched controls (93 +/- 3 vs. 83 +/- 5 mmHg, P < 0.05). Mesenteric arteries from the steroid-exposed fetuses displayed diminished responses to ANG II, relative to controls. In 4-mo-old lambs, prenatal dexamethasone exposure significantly increased coronary artery vasoconstriction to ANG II, ACh, and U-46619, but not KCl. In contrast, postnatal mesenteric artery reactivity was unaltered by steroid exposure. Compared with fetal mesenteric reactivity, postnatal mesenteric reactivity to ANG II, phenylephrine, and U-46619 was diminished, whereas the response to 120 mmol/l KCl was heightened. Coronary artery ANG II receptor protein expression was not significantly altered by steroid exposure in either age group. These findings demonstrate that early-gestation glucocorticoid exposure programs postnatal elevations in blood pressure and selectively enhances coronary artery responsiveness to second messenger-dependent vasoconstrictors. Glucocorticoid-induced alterations in coronary vascular smooth muscle structure or function may provide a mechanistic link between an adverse intrauterine environment and later cardiovascular disease.

Author List

Roghair RD, Lamb FS, Miller FJ Jr, Scholz TD, Segar JL

Author

Jeffrey L. Segar MD Professor in the Pediatrics department at Medical College of Wisconsin




MESH terms used to index this publication - Major topics in bold

Angiotensin II
Animals
Carotid Arteries
Coronary Vessels
Dexamethasone
Female
Fetus
Gestational Age
Glucocorticoids
Mesenteric Arteries
Pregnancy
Prenatal Exposure Delayed Effects
Sheep
Vascular Resistance
Vasoconstriction
jenkins-FCD Prod-478 d1509cf07a111124a2d122fd3df854cc0b993c00