Effects of high and low 17β-estradiol doses on focal cerebral ischemia in rats

Scientific Reports
Edvin IngbergJakob O Strom

Abstract

The majority of the numerous animal studies of the effects of estrogens on cerebral ischemia have reported neuroprotective results, but a few have shown increased damage. Differences in hormone administration methods, resulting in highly different 17β-estradiol levels, may explain the discrepancies in previously reported effects. The objective of the present study was to test the hypothesis that it is the delivered dose per se, and not the route and method of administration, that determines the effect, and that high doses are damaging while lower doses are protective. One hundred and twenty ovariectomized female Wistar rats (n = 40 per group) were randomized into three groups, subcutaneously administered different doses of 17β-estradiol and subjected to transient middle cerebral artery occlusion. The modified sticky tape test was performed after 24 h and the rats were subsequently sacrificed for infarct size measurements. In contrast to our hypothesis, a significant negative correlation between 17β-estradiol dose and infarct size was found (p = 0.018). Thus, no support was found for the hypothesis that 17β-estradiol can be both neuroprotective and neurotoxic merely depending on dose. In fact, on the contrary, the findings indic...Continue Reading

References

Jan 1, 1989·Stroke; a Journal of Cerebral Circulation·E Z LongaR Cummins
Jan 1, 1984·Acta Neuropathologica·T M LiszczakN T Zervas
Sep 1, 1996·Stroke; a Journal of Cerebral Circulation·E J GoldlustM P Goldberg
Dec 3, 1999·Stroke; a Journal of Cerebral Circulation·UNKNOWN Stroke Therapy Academic Industry Roundtable (STAIR)
Jul 8, 2000·Neuropathology and Applied Neurobiology·B S AspeyM J Harrison
Sep 20, 2000·Biology of Reproduction·P M Wise, D B Dubal
Nov 4, 2000·Stroke; a Journal of Cerebral Circulation·T K ToungF E Sieber
Jun 5, 2002·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·Toru MatsuiTakao Asano
Jan 11, 2005·BMJ : British Medical Journal·Philip M W Bath, Laura J Gray
Jan 14, 2005·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·Deborah BinghamHilary V Carswell
Feb 24, 2005·Brain Research·Kirsty B GordonHilary V O Carswell
Jan 27, 2006·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·Claire L GibsonPhilip M W Bath
Feb 3, 2006·Annals of Neurology·Victoria E O'CollinsDavid W Howells
Feb 16, 2006·Journal of Neuroscience Methods·Michael E SughrueE Sander Connolly
Aug 16, 2008·Stroke; a Journal of Cerebral Circulation·Malcolm R MacleodDavid W Howells
Sep 30, 2008·Scandinavian Journal of Clinical and Laboratory Investigation·Jakob O StrömAnnette Theodorsson
Apr 30, 2009·Frontiers in Neuroendocrinology·Shotaro SuzukiPhyllis M Wise
May 22, 2009·Journal of Cerebral Blood Flow and Metabolism : Official Journal of the International Society of Cerebral Blood Flow and Metabolism·Jakob O StromElvar Theodorsson
Sep 8, 2010·Journal of Neuroscience Methods·Matthew BoykoVivian I Teichberg
Aug 13, 2011·Scandinavian Journal of Clinical and Laboratory Investigation·Ida-Maria IsakssonJakob O Strom
Sep 22, 2011·Endocrinology·Daniel J HaisenlederJohn C Marshall
Dec 6, 2011·General and Comparative Endocrinology·E IngbergJ O Strom
Jan 4, 2012·World Neurosurgery·Debraj Mukherjee, Chirag G Patil
Jun 20, 2012·Journal of Visualized Experiments : JoVE·Jakob O StrömElvar Theodorsson
Nov 2, 2013·Scientific Reports·Jakob O StromAnnette Theodorsson
Mar 22, 2014·Stroke; a Journal of Cerebral Circulation·Ulrich Dirnagl, Matthias Endres

❮ Previous
Next ❯

Methods Mentioned

BETA
ELISA
enzyme-linked

Software Mentioned

Systat
ScanJet
SigmaScan Pro
Random Sequence Generator

Related Concepts

Related Feeds

Brain Ischemia

Brain ischemia is a condition in which there is insufficient blood flow to the brain to meet metabolic demand. Discover the latest research on brain ischemia here.