Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-8-22
pubmed:abstractText
Ischaemia was induced to the rat retina by raising the intraocular pressure above the systolic blood pressure for 45 min. After a reperfusion period of 5 days, alterations in the localisation of choline acetyltransferase (ChAT) and calretinin immunoreactivities, a reduction in the thickness of the inner retinal layers and a decline in the b-wave amplitude of the electroretinogram were recorded. These changes were blunted when clonidine was injected intraperitoneally before or after ischaemia or when applied topically by a specific regime. Other alpha(2)-adrenoceptor agonists, brimonidine and apraclonidine, acted in a similar way to clonidine when applied topically but because of the number of experiments carried out a comparison between the effectiveness of the different alpha(2)-adrenoceptor agonists was not possible. The protective effect of clonidine was attenuated when the alpha(2)-adrenoceptor antagonists yohimbine or rauwolscine were co-administered, suggesting that the mechanism of action of the drug is to stimulate alpha(2)-adrenoceptors. In addition, the imidazoline receptor ligands, BU-226 and AGN-192403 did not blunt the effect of ischaemia/reperfusion, supporting the notion that the protective action of the alpha(2)-adrenoceptor agonists does not involve imidazoline sites but rather the activation of alpha(2)-adrenoceptors. The protective effect of 0.5% clonidine appeared to be greater when topically applied to the eye that received ischaemia than when applied by the same regime to the contralateral eye. These studies suggest that while most of topically applied clonidine reaches the retina by a systemic route one cannot rule out additional pathways.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/AGN 192403, http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-Agonists, http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic alpha-Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Bicyclo Compounds, http://linkedlifedata.com/resource/pubmed/chemical/Calcium-Binding Protein, Vitamin..., http://linkedlifedata.com/resource/pubmed/chemical/Choline O-Acetyltransferase, http://linkedlifedata.com/resource/pubmed/chemical/Clonidine, http://linkedlifedata.com/resource/pubmed/chemical/Heptanes, http://linkedlifedata.com/resource/pubmed/chemical/Imidazoline Receptors, http://linkedlifedata.com/resource/pubmed/chemical/Neuroprotective Agents, http://linkedlifedata.com/resource/pubmed/chemical/Quinoxalines, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Adrenergic, alpha-2, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Drug, http://linkedlifedata.com/resource/pubmed/chemical/Yohimbine, http://linkedlifedata.com/resource/pubmed/chemical/apraclonidine, http://linkedlifedata.com/resource/pubmed/chemical/brimonidine, http://linkedlifedata.com/resource/pubmed/chemical/calretinin
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
904
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
126-36
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:11516418-Adrenergic alpha-Agonists, pubmed-meshheading:11516418-Adrenergic alpha-Antagonists, pubmed-meshheading:11516418-Animals, pubmed-meshheading:11516418-Bicyclo Compounds, pubmed-meshheading:11516418-Calcium-Binding Protein, Vitamin D-Dependent, pubmed-meshheading:11516418-Cell Death, pubmed-meshheading:11516418-Choline O-Acetyltransferase, pubmed-meshheading:11516418-Clonidine, pubmed-meshheading:11516418-Electroretinography, pubmed-meshheading:11516418-Heptanes, pubmed-meshheading:11516418-Imidazoline Receptors, pubmed-meshheading:11516418-Immunohistochemistry, pubmed-meshheading:11516418-Membrane Potentials, pubmed-meshheading:11516418-Nerve Degeneration, pubmed-meshheading:11516418-Neuroprotective Agents, pubmed-meshheading:11516418-Quinoxalines, pubmed-meshheading:11516418-Rats, pubmed-meshheading:11516418-Rats, Wistar, pubmed-meshheading:11516418-Receptors, Adrenergic, alpha-2, pubmed-meshheading:11516418-Receptors, Drug, pubmed-meshheading:11516418-Reperfusion Injury, pubmed-meshheading:11516418-Retina, pubmed-meshheading:11516418-Retinal Ganglion Cells, pubmed-meshheading:11516418-Yohimbine
pubmed:year
2001
pubmed:articleTitle
Topically applied clonidine protects the rat retina from ischaemia/reperfusion by stimulating alpha(2)-adrenoceptors and not by an action on imidazoline receptors.
pubmed:affiliation
Nuffield Laboratory of Ophthalmology, University of Oxford, Walton Street, OX2 6AW, Oxford, UK.
pubmed:publicationType
Journal Article