Liquid crystalline properties of chlorpromazine-doped erythrocyte lipids

Abstract

Liquid crystals may be defined as another state of matter having characteristics of both liquid and crystalline solid, in that it has some degree of order but also some degree of fluidity. "The combination of flow and lability with a preferred and relatively stable molecular orientation" makes liquid crystals apt for the structure of protoplasm and living tissue. The lipid components of the rods and the cones of the eye, chloroplasts, erythrocytes, certain other cellular organelles and serum lipoproteins have shown organization, which is related to the molecular structure of liquid crystals.
Red blood cell or erythrocyte membranes have been extensively studied since the cells can be effortlessly obtained by venous puncture and the membranes are easily isolated by low speed centrifugation. The human erythrocyte, having only one membrane, has no internal structure. Thus, its shape is solely based on the physical properties of the membrane and the cell volume.
Erythrocytes have become good models for drug membrane interaction, especially when the drugs under study have their site of action at the membrane level, such as antipsychotic agents and local anesthetics. The pharmacological effects of drugs ultimately depend on drug-protein interactions. However, drug molecules must cross lipid membrane barriers before reaching the target site. Thus, the interactions of drugs with phospholipids and phospholipid-containing membranes, i.e. erythrocyte membranes, play critical roles in drug disposition and drug action.
This study aims to characterize the liquid crystalline properties of erythrocyte ghosts and lipids. It also intends to observe the changes in the liquid crystalline properties of erythrocyte lipids upon addition of chlorpromazine, an antipsychotic amphiphilic drug.