Relative muscarinic synaptic activation by anionic, neutral or cationic liposomes.
Liposomes made of dipalmitoyl phosphatidyl choline (DPC) and safflower oil fatty acids produce a contraction of the guinea pig ileum longitudinal muscle myenteric plexus preparation (LMMP). Stimulating the LMMP while liposomes are present yielded greater than control contractions, an effect which remained for many minutes after liposomes had been washed out. Neutral (DPC) liposomes produced a direct transitory decrease in basal tension and phasic activity. Stimulation in the presence of neutral liposomes resulted in slower attainment of maximal contraction. Cationic liposomes(DPC + oleylamine) had little direct effect, but slightly decreased stimulus evoked maximal contraction.
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D005227:Fatty Acids / Q000494:pharmacology*; D006168:Guinea Pigs; D007082:Ileum / Q000294:innervation; D008081:Liposomes; D009119:Muscle Contraction / Q000187:drug effects; D009197:Myenteric Plexus / Q000187:drug effects / Q000502:physiology*; D011663:Pulmonary Surfactants / Q000494:pharmacology*; D011950:Receptors, Cholinergic / Q000502:physiology*; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000187:drug effects / Q000502:physiology*
D005227:Fatty Acids; D008081:Liposomes; D011663:Pulmonary Surfactants; D011950:Receptors, Cholinergic; D011976:Receptors, Muscarinic; D000109:Acetylcholine