Developing lipid composition

The lipid compositions of plasma membranes, endoplasmic reticulum and Golgi membranes are distinct 26 Cholesterol transport and regulation in the central nervous system is distinct from that of peripheral tissues 26 In adult brain most cholesterol synthesis occurs in astrocytes 26 The astrocytic cholesterol supply to neurons is important for neuronal development and remodeling 27 The structure and roles of membrane microdomains (rafts) in cell membranes are under intensive study but many aspects are still unresolved 28... 

Eukaryotic cells have evolved a complex, intracellular membrane organization. This organization is partially achieved by compartmentalization of cellular processes within specialized membrane-bounded organelles. Each organelle has a unique protein and lipid composition. This internal membrane system allows cells to perform two essential functions to sort and deliver fully processed membrane proteins, lipids and carbohydrates to specific intracellular compartments, the plasma membrane and the cell exterior, and to uptake macromolecules from the cell exterior (reviewed in [1,2]). Both processes are highly developed in cells of the nervous system, playing critical roles in the function and even survival of neurons and glia. 

Recently, a cell culture derived from biopsies of healthy human buccal mucosa has been developed with remarkably similar morphology, membranecoating granule structure and appearance, and lipid composition to intact buccal tissue [102], The barrier nature of this cell culture model is similar to intact buccal mucosa, and so this cell culture may be an alternative model to the... 

The affinity of certain drugs to tissues with a particular lipid composition, which can lead to unwanted accumulation and toxicity, can, under certain circumstances, be an advantage for the development of drugs with particular selectivity, provided the specific receptor is located in such a membrane and is accessible for the drug. 

However, similar changes in lipid composition are possible using a variety of other cell types (Bums and Wagner, 1993) such as an adenocarcinoma (Awad and Spector, 1976), and hepatoma (Wood et al, 1975). The dietary fatty acid modification is not limited to tumor cells, since many tissues of the host are affected (Bums et al., 1983). However, different tissues are modified to varying extents, and because of this it will likely be possible to develop protocols that provide therapeutic selectivity by producing greater or lesser enrichment of the neoplastic cells with a particular type of fatty acid as compared to normal tissues. We have also demonstrated that L1210 leukemia cells that were fatty acid modified in vivo and then placed into tissue culture maintain their experimentally-induced fatty acid composition for up to 4 days (Bums et al, 1980). Therefore, this is a versatile model. 

We shall now explore the dynamics between lipid composition of the mature female and her developing oocytes, with a focus on POP distribution into the developing oocytes. Are the offspring of one species at greater risk of exposure to POP compared to another s because of their mothers total body lipid ... 

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