Effect of prostaglandin E1, dopamine and dibutyryl cyclic AMP on the fluidity of synaptosome membranes.
The membrane fluidity of synaptosomes, isolated from rat brain and spin-labelled with doxyl derivatives of stearic acid, was studied using electron spin resonance techniques. Prostaglandin E1 fluidized while dopamine ordered both the surface and intermediate lipid layers of the synaptosome membranes. At corresponding concentrations these substances have been shown to modulate synaptic transmission. A possible thermal phase transition of the membrane lipid bilayer was observed at about 35 degrees C (the abrupt change in the Arrhenius plot). Dopamine abolished this thermal change. Dibutyryl cyclic AMP had no significant membrane effects.
D000527:Alprostadil; D000818:Animals; D001921:Brain / Q000166:cytology; D003994:Bucladesine / Q000494:pharmacology*; D002469:Cell Separation; D004298:Dopamine / Q000494:pharmacology*; D004578:Electron Spin Resonance Spectroscopy; D050356:Lipid Metabolism; D008297:Male; D018377:Neurotransmitter Agents / Q000378:metabolism; D011458:Prostaglandins E / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D013570:Synaptic Membranes / Q000187:drug effects* / Q000378:metabolism; D013574:Synaptosomes / Q000187:drug effects*; D013696:Temperature
D018377:Neurotransmitter Agents; D011458:Prostaglandins E; D003994:Bucladesine; D000527:Alprostadil; D004298:Dopamine