The study was funded by Link&ouml;ping University and the County Council of &Ouml;sterg&ouml;tland.

1. Ovariectomy via the Dorsal Route
<ol>
	<li>Anesthetize the animal, for example using 1.5% isoflurane (4% for induction) in an oxygen/nitrous oxide 30%/70% mixture. Place the animal in prone position on a heating plate connected to a rectal thermometer. It is important to have a thin layer of isolation between the animal and the plate, and that the thermometer feed-back system keeps the body temperature within 37 &plusmn; 0.5 &deg;C. Apply gel for eye protection and administer 5 mg Rimadyl/kg bodyweight diluted in sa...

<ol>
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O., Theodorsson, E., Holm, L., Theodorsson, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Different+methods+for+administering+17beta-estradiol+to+ovariectomized+rats+result+in+opposite+effects+on+ischemic+brain+damage.">Different methods for administering 17beta-estradiol to ovariectomized rats result in opposite effects on ischemic brain damage.</a> BMC Neurosci. 11, 1471-2202 (2010).</li><li>Strom, J. O., Theodorsson, A., Theodorsson, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Hormesis+and+Female+Sex+Hormones.">Hormesis and Female Sex Hormones.</a> Pharmaceuticals. 4, 15 (2011).</li><li>Isaksson, I. M., Theodorsson, A., Theodorsson, E., Strom, J. 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O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Methods+for+long-term+17beta-estradiol+administration+to+mice.">Methods for long-term 17beta-estradiol administration to mice.</a> General and comparative endocrinology. , (2011).</li><li>Kalliokoski, O., Jacobsen, K. R., Hau, J., Abelson, K. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Serum+concentrations+of+buprenorphine+after+oral+and+parenteral+administration+in+male+mice.">Serum concentrations of buprenorphine after oral and parenteral administration in male mice.</a> Vet. J. 187, 251-254 (2011).</li><li>Simpkins, J. 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V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Differential+effects+of+17beta-estradiol+upon+stroke+damage+in+stroke+prone+and+normotensive+rats.">Differential effects of 17beta-estradiol upon stroke damage in stroke prone and normotensive rats.</a> J. Cereb. Blood Flow Metab. 24, 298-304 (2004).</li><li>Yong, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=17beta-estradiol+potentiates+ischemia-reperfusion+injury+in+diabetic+ovariectomized+female+rats.">17beta-estradiol potentiates ischemia-reperfusion injury in diabetic ovariectomized female rats.</a> Brain Res. 1054, 192-199 (2005).</li><li>Theodorsson, A., Theodorsson, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Estradiol+increases+brain+lesions+in+the+cortex+and+lateral+striatum+after+transient+occlusion+of+the+middle+cerebral+artery+in+rats:+no+effect+of+ischemia+on+galanin+in+the+stroke+area+but+decreased+levels+in+the+hippocampus.">Estradiol increases brain lesions in the cortex and lateral striatum after transient occlusion of the middle cerebral artery in rats: no effect of ischemia on galanin in the stroke area but decreased levels in the hippocampus.</a> Peptides. 26, 2257-2264 (2005).</li><li>Levin-Allerhand, J. 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The administration modes presented above have in earlier studies proved superior to commercial slow-release pellets and injections in terms of producing physiological serum concentrations of 17&beta;-estradiol. While the slow-release pellets produce very high and prolonged serum concentration peaks, the injections cause extreme, daily hormone fluctuations and require repeated stressful handling of the animals 4-6. The importance of choosing adequate administration modes is highlighted by recent studies indicat...

<table border="1">
 <tbody>
 <tr>
 <td>Name of the reagent</td>
 <td>Company</td>
 <td>Catalogue number</td>
 <td>Comments</td>
 </tr>
 <tr>
 <td>Rimadyl, 50 mg/mL</td>
 <td>Pfizer</td>
 <td>462986</td>
 <td>Postoperative analgesia after ovariectomy.</td>
 </tr>
 <tr>
 <td>Lubrithal eye gel</td>
 <td>Leo Laboratories </td>
 <td>&nbsp;</td>
 <td>Eye protection during surgery.</td>
 </tr>
 <tr>
 <td>Jodopax vet</td>
 <td>Pharmaxim </td>
 <td>&nbsp;</td>
 <td>Surgery disinfection.</td>
 </tr>
 <tr>
 <td>Vicryl 4-0 suture</td>
 <td>Johnson &amp; Johnson</td>
 <td>&nbsp;</td>
 <td>Wound suture and ovary ligation.</td>
 </tr>
 <tr>
 <td>17&beta;-estradiol, &gt;98%</td>
 <td>Sigma</td>
 <td>E8875-1G</td>
 <td>In sesame oil for silastic capsules and Nutella.</td>
 </tr>
 <tr>
 <td>Sesame oil</td>
 <td>Sigma</td>
 <td>S3547-1L</td>
 <td>Dissolving the 17&beta;-estradiol.</td>
 </tr>
 <tr>
 <td>Silastic tubing, ID/OD: 1.575/3.175 mm</td>
 <td>Dow Corning</td>
 <td>508-008</td>
 <td>Production of silastic capsules.</td>
 </tr>
 <tr>
 <td>Wooden applicator stick</td>
 <td>Selefatrade</td>
 <td>12-0783</td>
 <td>Capping of silastic capsules.</td>
 </tr>
 <tr>
 <td>Nutella</td>
 <td>Ferrero</td>
 <td>&nbsp;</td>
 <td>Medium for peroral 17&beta;-estradiol.</td>
 </tr>
 </tbody>
</table>

ovariectomy and 17&beta;-estradiol replacement in rats and mice: a visual demonstration

Estrogens are a family of female sexual hormones with an exceptionally wide spectrum of effects. When rats and mice are used in estrogen research they are commonly ovariectomized in order to ablate the rapidly cycling hormone production, replacing the 17&beta;-estradiol exogenously. There is, however, lack of consensus regarding how the hormone should be administered to obtain physiological serum concentrations. This is crucial since the 17&beta;-estradiol level/administration method profoundly influences the experimental results1-3. We have in a series of studies characterized the different modes of 17&beta;-estradiol administration, finding that subcutaneous silastic capsules and per-oral nut-cream Nutella are superior to commercially available slow-release pellets (produced by the company Innovative Research of America) and daily injections in terms of producing physiological serum concentrations of 17&beta;-estradiol4-6. Amongst the advantages of the nut-cream method, that previously has been used for buprenorphine administration7, is that when used for estrogen administration it resembles peroral hormone replacement therapy and is non-invasive. The subcutaneous silastic capsules are convenient and produce the most stable serum concentrations. This video article contains step-by-step demonstrations of ovariectomy and 17&beta;-estradiol hormone replacement by silastic capsules and peroral Nutella in rats and mice, followed by a discussion of important aspects of the administration procedures.

Watch this Scientific Journal Video about Ovariectomy and 17Î²-estradiol Replacement in Rats and Mice: A Visual Demonstration at JoVE.com

Ovariectomy and 17&amp;#946;-estradiol Replacement in Rats and Mice: A Visual Demonstration

Ovariectomy and subsequent replacement of 17&beta;-estradiol by means of silastic capsules and peroral Nutella are demonstrated in rats and mice.

Ovariectomy and 17&beta;-estradiol Replacement in Rats and Mice: A Visual Demonstration

Estrogens are a family of female sexual hormones with an exceptionally wide spectrum of effects. When rats and mice are used in estrogen research they are ...

ovariectomy-17-estradiol-replacement-rats-mice-visual

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56.4K visualizações.  Linköping University. Ovariectomia e subsequente substituição do 17β-estradiol, por meio de cápsulas de silastic e Nutella perorai são demonstrados em ratos e ratinhos.