We have located links that may give you full text access.
IN VITRO
JOURNAL ARTICLE
RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Impaired oxygen-dependent reduction of HIF-1alpha and -2alpha proteins in pre-eclamptic placentae.
Placenta 2003 Februrary
Pre-eclamptic (PE) placentae overexpress hypoxia inducible transcription factors-1alpha and -2alpha proteins (Biol. Repro. 64: 499-506, 2001; Ibid 1019-1020). Possible explanations include (a) impaired oxygen-dependent reduction, and/or (b) enhanced sensitivity to reduced oxygen. After 18 h equilibration under 21 per cent O(2) atmosphere, we subjected villous explants prepared from placentae of normal pregnant (NP) and pre-eclamptic (PE) women (n=8 each) to 4h of hypoxia (2 per cent oxygen), and then studied the disappearance of HIF-1alpha and -2alpha proteins during subsequent oxygenation over 90 min (21 per cent oxygen). The disappearance of these HIF proteins as assessed by Western analysis was significantly impaired in the pre-eclamptic tissues. Even after 18h equilibration under a 21 per cent O(2) atmosphere, and then a further 4h at 21 per cent O(2), HIF-1alpha and -2alpha protein expression remained increased in villous explants from PE women (both P< 0.04 vs NP). To address whether chronic hypoxia per se (which is believed to exist in the pre-eclamptic placenta) might contribute to these findings, we subjected villous explants from normal placentae (n=6) to 18 h preincubation under 2 per cent or 21 per cent oxygen prior to subsequent incubation for 4h at 2 per cent oxygen and then 90 min at 21 per cent oxygen. The time course of disappearance of HIF proteins during oxygenation was similar irrespective of the 2 per cent or 21 per cent preconditioning. To evaluate oxygen sensitivity, we exposed villous explants from NP and PE women (n=6 each) to different oxygen atmospheres for 4h and measured HIF protein induction. Although the data showed a significant inverse relationship between HIF expression and oxygen concentration, there was no significant difference between the slopes of this relationship for the two groups of women. We conclude that villous explants from PE placentae fail to adequately downregulate HIF protein expression upon oxygenation. This abnormality may contribute to their overexpression in vivo.
Full text links
Related Resources
Trending Papers
Heart failure with preserved ejection fraction: diagnosis, risk assessment, and treatment.Clinical Research in Cardiology : Official Journal of the German Cardiac Society 2024 April 12
Proximal versus distal diuretics in congestive heart failure.Nephrology, Dialysis, Transplantation 2024 Februrary 30
Efficacy and safety of pharmacotherapy in chronic insomnia: A review of clinical guidelines and case reports.Mental Health Clinician 2023 October
World Health Organization and International Consensus Classification of eosinophilic disorders: 2024 update on diagnosis, risk stratification, and management.American Journal of Hematology 2024 March 30
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app
All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.
By using this service, you agree to our terms of use and privacy policy.
Your Privacy Choices
You can now claim free CME credits for this literature searchClaim now
Get seemless 1-tap access through your institution/university
For the best experience, use the Read mobile app