Sphingosine induced release of K+ and 5-HT in platelets should not be confused with membrane leakiness.
The release of 43K+, lactate dehydrogenase (LDH) and [14C]-5-hydroxytryptamine ([14C]-5-HT) from platelets treated with sphingosine and four differently charged model amphiphiles was studied. Sphingosine was found to differ from the detergents because it induced a concentration-dependent release of both 43K+ and [14C]-5-HT without causing a release of LDH. The release of [14C]-5-HT preceded the release of 43K+ and it is concluded that these effects are associated with platelet activation. The detergents caused a release of 43K+ followed by a release of LDH without causing a release of [14C]-5-HT. These effects are attributed to a non-specific perturbation of the platelet plasma membrane.
Mäkelä
J H
JH
Department of Biology, Abo Akademi University, BIOCITY, Finland.
Isomaa
B
B
D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects; D002463:Cell Membrane Permeability / Q000187:drug effects*; D003902:Detergents / Q000494:pharmacology; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000097:blood; D015539:Platelet Activation / Q000187:drug effects; D011188:Potassium / Q000097:blood*; D012701:Serotonin / Q000097:blood*; D013110:Sphingosine / Q000494:pharmacology*
D003902:Detergents; D012701:Serotonin; D007770:L-Lactate Dehydrogenase; D013110:Sphingosine; D011188:Potassium