Linked Life Data

8968591

Source:http://linkedlifedata.com/resource/pubmed/id/8968591

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1997-4-7
pubmed:abstractText
The effect of cholesterol on the bilayer phase behavior of heteroacid phosphatidylcholines with one unsaturated fatty acid depends on the nature of the unsaturated chain. Previous differential scanning calorimetry (DSC) studies showed that 1-palmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (16:0-18:2 PC) had a broad, weak transition at about -18 degrees C, which was effectively eliminated by less than 15 mol% cholesterol. Phospholipids with greater and lesser degrees of unsaturation displayed stronger phase transitions and less sensitivity to cholesterol. In this work, deuterium nuclear magnetic resonance has been used to examine the phase behavior of 1-perdeuteriopalmitoyl-2-linoleoyl-sn-glycero-3-phosphocholine (16:0-18:2 PC-d31) alone, and with 15 mol % cholesterol. The behavior is found to be sensitive to sample thermal history. Moderately fast cooling (1 degree/h) results in a continuous phase change from a fluid to an ordered phase in the pure lipid. Under similar cooling conditions, the sample containing cholesterol displays increased chain order and a continuous phase change with no apparent isothermal transition. However, when these systems are cooled at a reduced rate (0.3 degree/h), the continuous phase change is pre-empted by a sharp transition into a more ordered phase that gives a deuterium spectrum having intensity at a value of the quadrupole-splitting characteristic of a rigid lattice system. In the pure lipid, this transition effectively coincides with the center of the continuous phase change. Addition of 15 mol % cholesterol lowers the temperature of this sharp transition by about 3 degrees C. These observations provide some insights into the behavior of this system seen using differential scanning calorimetry. Results of deuteron transverse relaxation measurements under these conditions are also reported.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-1420865, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-1691657, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-1709361, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-2261450, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-263690, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-2758050, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-3904832, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-3947630, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-4006876, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-4711186, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-570854, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-6337629, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-6488416, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-8155667, http://linkedlifedata.com/resource/pubmed/commentcorrection/8968591-8274498
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-3495
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3207-14
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Thermal history alters cholesterol effect on transition of 1-palmitoyl-2-linoleoyl phosphatidylcholine.
pubmed:affiliation
Department of Physics, Memorial University of Newfoundland, St. John's, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't