Hi Folks,
 
I have a couple of results which I am having trouble explaining and I hope
someone can put me right.  I use live tissue (blood vessels and smooth
muscle cells) on our confocal and recently have been using the probes
Hoechst 33342 (UV,nuclei), FITC-BSA (extracellular) and BODIPY FL-prazosin
(an alpha1-adrenoceptor ligand).  When I use Hoechst with either FITC or
BODIPY I often observe nuclear staining in the 488/515 range.  From the
mole probes handbook it would appear that the FITC and BODIPY may be
binding to thiolated nucleic acid.  My questions are;
 
i.      Why do I only see this when I have double labelled with Hoechst and
a                   Fluorescein.
ii.     How does nucleic acid become thiolated.
iii.    How does BODIPY and FITC get into live cells (receptor
internalisation or membrane transport?) both probes are supposed to be
impermeant.
 
If you are still reading this, do you use Fluorescent ligands for
receptors?  If so are you interested in receptor localisation and
pharmacology?  We are trying to develop a method of real time ligand
binding using fluorescent probes for receptors and would like to make
contact with anyone who has a similar interest.
 
Thanks for taking the time to read this.
 
Craig.
 
 
 
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Craig J. Daly
Research Associate,
CRI Heart Failure,
Institute of Physiology,
University of Glasgow,
Glasgow G12 8QQ                 Tel. 44 41 339 8855 ext 6606
                                Fax. 44 41 330 4100
                                [log in to unmask]
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