title: GRK2 levels in umbilical arteries of pregnancies complicated by gestational hypertension and preeclampsia.
abstract: BACKGROUND
  G-Protein coupled receptor kinase 2 (GRK2) represents a regulator of cell function in different cardiovascular conditions, including high blood pressure. The relationship between elevated GRK2 levels and impaired vasorelaxant responses is causative of hypertension through the increase in vascular resistances. The aim of this study is to ascertain if this feature is present in the fetal placental vasculature of pregnancies complicated by hypertensive disorders.
  
  
  METHODS
  We have assessed GRK2 levels in the umbilical arteries (UA) of 21 preeclamptic or gestational hypertensive and 23 normotensive women at time of delivery.
  
  
  RESULTS
  GRK2 levels were increased in the hypertensive group (0.83 ± 0.14 vs. 0.48 ± 0.06 densitometry units; P < 0.05). GRK2 levels were in correlation and in linear regression with systolic, diastolic, and mean arterial pressure (P < 0.05, r(2) = 0.12, r(2) = 0.11, r(2) = 0.12). Correlations did not reach a significant value for other clinical parameters such as gestational age at birth, umbilical artery pulsatility index, maternal proteinuria, and neonatal birth weight. Out of the 21 hypertensive women, 7 who developed a preeclampsia associated with early preterm delivery (before 34 weeks) had a significantly lower GRK2 levels compared to the remaining 14 (0.51 ± 0.12 vs. 1.08 ± 0.20 densitometry units, P < 0.05).
  
  
  CONCLUSIONS
  We conclude that elevated GRK2 levels in the umbilical vasculature is correlated to elevated blood pressure levels, with a likely compensatory rather than causative role since the lack of protective effect of elevated GRK2 levels may negatively affect the outcome of the hypertensive state.
authors.affiliation: Department of Obstetrics and Gynecology, Prenatal Diagnosis and High Risk Pregnancy Unit, University of Naples, Federico II, Naples, Italy.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Napolitano
authors.forename: Alfonso
authors.initials: A
authors.lastname: Campanile
authors.forename: Laura
authors.initials: L
authors.lastname: Sarno
authors.forename: Antonio
authors.initials: A
authors.lastname: Anastasio
authors.forename: Giuseppe M
authors.initials: GM
authors.lastname: Maruotti
authors.forename: Maddalena
authors.initials: M
authors.lastname: Morlando
authors.forename: Bruno
authors.initials: B
authors.lastname: Trimarco
authors.forename: Pasquale
authors.initials: P
authors.lastname: Martinelli
authors.forename: Guido
authors.initials: G
authors.lastname: Iaccarino
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D054769:G-Protein-Coupled Receptor Kinase 2 / Q000378:metabolism*; D006801:Humans; D046110:Hypertension, Pregnancy-Induced / Q000378:metabolism*; D011225:Pre-Eclampsia / Q000378:metabolism*; D011247:Pregnancy; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D014469:Umbilical Arteries / Q000378:metabolism*
chemical_list: D011943:Receptors, Adrenergic, beta; C496567:GRK2 protein, human; D054769:G-Protein-Coupled Receptor Kinase 2