Alterations of muscarinic synaptic activity by anionic liposomes.
Liposomes made of phosphatidyl serine and dioleylphosphatidic acid have two effects on contraction of the guinea pig ileum longitudinal muscle-myenteric plexus preparation. First, the liposomes directly stimulate contraction, apparently through acetylcholine release. Second, after the liposomes are removed from the Tyrode solution bathing the preparation, electrical field stimulation or acetylcholine addition produce contractions which are significantly less than control. The acetylcholine release effect is presynaptic, on the nerve terminal, while the decreased responsiveness effect is postsynaptic, at the level of the muscarinic receptor.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D000838:Anions; D001285:Atropine / Q000494:pharmacology; D004558:Electric Stimulation; D006168:Guinea Pigs; D008081:Liposomes / Q000494:pharmacology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D010712:Phosphatidic Acids / Q000494:pharmacology; D010718:Phosphatidylserines / Q000494:pharmacology; D011950:Receptors, Cholinergic / Q000187:drug effects*; D011976:Receptors, Muscarinic / Q000187:drug effects*; D013569:Synapses / Q000187:drug effects*
D000838:Anions; D008081:Liposomes; D010712:Phosphatidic Acids; D010718:Phosphatidylserines; D011950:Receptors, Cholinergic; D011976:Receptors, Muscarinic; D001285:Atropine; D000109:Acetylcholine