In artificial phospholipid bilayers, dual measurements of laurdan steady-state anisotropy and emission spectra can be used to identify the presence of liquid ordered phases. Human erythrocytes were used as a model to test whether similar measurements could be applied to biological samples. Specifically, laurdan anisotropy and emission spectra were obtained from native erythrocytes before and after treatment with calcium ionophore and from the microvesicles (known to be enriched in liquid ordered domains) shed from the cells during calcium entry. Spectral and anisotropy data were consistent with an increased order and reduced fluidity of erythrocyte membrane lipids upon ionophore treatment. Microvesicle membranes appeared more ordered than native erythrocytes and similar to ionophore-treated cells based on laurdan emission. In contrast, the anisotropy value was lower in microvesicles compared to ionophore-treated cells, suggesting greater probe mobility. Parallel measurements of diphenylhexatriene anisotropy corroborated the laurdan data. These results were consistent with the liquid ordered property of microvesicle membranes based on comparisons to behavior in artificial membranes. Two-photon microscopy was used to examine the distribution of laurdan fluorescence along the surface of erythrocyte membranes before and after ionophore treatment. A dual spatial analysis of laurdan anisotropy, as revealed by the distribution of laurdan emission spectra, and intensity excited by polarized light suggested that the plasma membranes of ionophore-treated erythrocytes may also exhibit elevated numbers of liquid ordered domains.
The Journal of Membrane Biology – Springer Journals
Published: Sep 18, 2006
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera