ABSTRACT
Unfortunately, for the time being we do not possess sufficiently extensive information revealing the role of LP0 reactions for the course of normal metabolic processes under physiological conditions. Therefore, this chapter will be short. Nevertheless, even leaving aside free-radical reactions in the bactericidal action of leukocytes, as well as the free-radical reactions of the free fatty acid peroxidation, taking place with the participation of cycloxygenases and lipoxygenases, and leading to the formation of physiologically active prostanoids and docosanoids with cyclic and aliphatic structure (prostaglandins, prostacyclins, thromboxanes, leukotrienes, lypoxines, and lipoxenes), we can adduce examples of the indisputable participation of the reactions of phospholipid peroxidation in the metabolism. However, it seems reasonable to discuss first in a more general way the following question: why do we estimate that LP0 reactions can be components of the network of normal metabolic pathways? What are the prerequisites for this? We can cite at least five such prerequisites:
1. LP0 products are present in the lipid phase of the membrane structures of different cells in vivo (see Chapter 1). Although the steady-state concentrations of the endogenous LP0 products are low, as a rule, under normal conditions, they nevertheless differ considerably from zero.
