Effect of Local Anesthetics on the Fluidity of Liposomal Membrane

다국어 초록 (Multilingual Abstract)

The effects of local anesthetics on the phase transition of liposomal lipid bilayer made of dipalmitoyl phosphatidylcholine was investigated with differential scanning calorimetry. The thermograms of the liposomal bilayer incorporated with procaine, lidocaine, tetracaine and dibucaine, respectively were obtained and the sizes of cooperative unit of the transition were calculated from the ratio of the van't Hoff enthalpy change to the calculated enthalpy change of the transition.
The results showed that incorporation of local anesthetics into the liposomal bilayer reduced the transition temperature at which the transition from solid state to liquid-crystalline state occurs, and broadened the thermogram peaks. Local anesthetics also significantly reduced the size of cooperative unit of the transition. This means that they might have significant fluidizing effects on the biomembrane. The sizes of cooperative unit were successfully correlated with pharmacological activities and the critical micelle concentrations of the local anesthetics. These correlations might be ascribed to a possible hydrophobic interaction between the biomembrane and the drugs involved in their pharmacology.

목차 (Table of Contents)

• Abstract
• Experimental = 41
• Results and Discussion = 42
• Acknowledgement = 44
• References = 45