The initiating event in preeclampsia is thought be to reduced uteroplacental perfusion. Although we have reported previously that chronic reductions in uterine perfusion pressure (RUPP) in pregnant rats results in hypertension and enhanced endothelin production, the factors linking placental ischemia and endothelial cell activation remain unclear. The purpose of this study was to determine the ...

Pregnancy impairs baroreflex gain, but the mechanism is incompletely understood. To test the hypothesis that reductions in brain insulin contribute, we determined whether pregnant rats exhibit lower cerebrospinal fluid (CSF) insulin concentrations and whether intracerebroventricular infusion of insulin normalizes gain of baroreflex control of heart rate in conscious pregnant rats. CSF insulin w...

Giardina, Jena B., Gachavis M. Green, Kathy L. Cockrell, Joey P. Granger, and Raouf A. Khalil. TNFenhances contraction and inhibits endothelial NO-cGMP relaxation in systemic vessels of pregnant rats. Am J Physiol Regulatory Integrative Comp Physiol 283: R130–R143, 2002. First published February 28, 2002; 10.1152/ajpregu.00704. 2001.—Tumor necrosis factor(TNF) is elevated in the plasma of preec...

Fos and dopamine β-hydroxylase immunoreactivity were evaluated in the brain stems of 21-day pregnant and virgin female rats injected with either hydralazine (HDZ; 10 mg/kg iv) or vehicle. HDZ produced significant hypotension in both groups, although baseline blood pressure was lower in pregnant rats (96 ± 2.5 mmHg) than in virgin female rats (121 ± 2.8 mmHg). There were no differences in Fos im...

OBJECTIVE An animal model for preeclampsia was developed by means of an ultra-low-dose endotoxin infusion protocol in conscious pregnant rats. STUDY DESIGN Rats received a permanent jugular vein cannula on day 0 of pregnancy, through which endotoxin (1.0 micrograms/kg body weight) (n = 10) or saline solution (n = 6) was infused during 1 hour on day 14 of pregnancy. Blood pressure, albuminuria...

Pregnancy impairs baroreflex gain, but the mechanism is incompletely understood. To test the hypothesis that reductions in brain insulin contribute, we determined whether pregnant rats exhibit lower cerebrospinal fluid (CSF) insulin concentrations and whether intracerebroventricular infusion of insulin normalizes gain of baroreflex control of heart rate in conscious pregnant rats. CSF insulin w...

During normal pregnancy, a gradual plasma volume expansion (VE) occurs and reaches a maximum level at late term. Pressure natriuresis and renal interstitial hydrostatic pressure (RIHP) responses are attenuated in pregnant rats. Also, basal RIHP is lower in pregnant rats, suggesting an increase in renal interstitial compliance during pregnancy. This adaptation may contribute to the increase in p...

Preeclampsia is associated with oxidative stress, which is suspected to play a role in hypertension, placental ischemia, and fetal demise associated with the disease. Various cellular sources of oxidative stress, such as neutrophils, monocytes, and CD4(+) T cells have been suggested as culprits in the pathophysiology of preeclampsia. The objective of this study was to examine a role of circulat...

As nitrogen metabolism is exacerbated during diabetes mellitus or/and pregnancy, and because arginase catalyses the arginine hydrolysis into ornithine and urea, this enzyme activity as well as the ornithine content were investigated in tissues (liver, kidney and brain) from pregnant or non pregnant streptozotocin (STZ) diabetic rats, dietary supplemented or not with antioxidant vitamins (C and ...

BACKGROUND Coronary flow reserve (CFR) is used as a measure of coronary endothelial function. We investigated the effect of increased afterload on CFR of pregnant and non-pregnant rats. METHODS Afterload increase in Wister rats (both pregnant and non-pregnant) was achieved by the infusion of angiotensin II (Ang II) for ∼10 days or by subjecting them to transverse aortic constriction (TAC) for...