OBJECTIVE: Examine temporal alterations in vascular angiotensin II receptors (AT(1)R and AT(2)R) and determine vascular response to angiotensin II in growth-restricted offspring. STUDY DESIGN: Offspring of pregnant rats fed low-protein (6%) and control (20%) diet were compared. RESULTS: Prenatal protein restriction reprogrammed AT(1a)R messenger RNA expression in male rats' mesenteric arteries to cause 1.7- and 2.3-fold increases at 3 and 6 months of age associated with arterial pressure increases of 10 and 33 mm Hg, respectively; however, in female rats, increased AT(1a)R expression (2-fold) and arterial pressure (15 mm Hg) occurred only at 6 months. Prenatal protein restriction did not affect AT(2)R expression. Losartan abolished hypertension, suggesting that AT(1a)R plays a primary role in arterial pressure elevation. Vasoconstriction to angiotensin II was exaggerated in all protein-restricted offspring, with greater potency and efficacy in male rats. CONCLUSION: Prenatal protein restriction increased vascular AT(1)R expression and vasoconstriction to angiotensin II, possibly contributing to programmed hypertension.
OBJECTIVE: Examine temporal alterations in vascular angiotensin II receptors (AT(1)R and AT(2)R) and determine vascular response to angiotensin II in growth-restricted offspring. STUDY DESIGN: Offspring of pregnant rats fed low-protein (6%) and control (20%) diet were compared. RESULTS: Prenatal protein restriction reprogrammed AT(1a)R messenger RNA expression in male rats' mesenteric arteries to cause 1.7- and 2.3-fold increases at 3 and 6 months of age associated with arterial pressure increases of 10 and 33 mm Hg, respectively; however, in female rats, increased AT(1a)R expression (2-fold) and arterial pressure (15 mm Hg) occurred only at 6 months. Prenatal protein restriction did not affect AT(2)R expression. Losartan abolished hypertension, suggesting that AT(1a)R plays a primary role in arterial pressure elevation. Vasoconstriction to angiotensin II was exaggerated in all protein-restricted offspring, with greater potency and efficacy in male rats. CONCLUSION: Prenatal protein restriction increased vascular AT(1)R expression and vasoconstriction to angiotensin II, possibly contributing to programmed hypertension.
Authors: P Pladys; F Sennlaub; S Brault; D Checchin; I Lahaie; N L O Lê; K Bibeau; G Cambonie; D Abran; M Brochu; G Thibault; P Hardy; S Chemtob; A M Nuyt Journal: Am J Physiol Regul Integr Comp Physiol Date: 2005-07-21 Impact factor: 3.619
Authors: C Yzydorczyk; F Gobeil; G Cambonie; I Lahaie; N L O Lê; S Samarani; A Ahmad; J C Lavoie; L L Oligny; P Pladys; P Hardy; A M Nuyt Journal: Am J Physiol Regul Integr Comp Physiol Date: 2006-06-01 Impact factor: 3.619