Basic Physiology of Eicosanoid Synthesis and Secretion

Moskowitz et al. (1983) demonstrated that phospholipase A2 in the presence of Ca++ was stimulated by calmodulin and PGp2 and inhibited by PGE2, cAMP and cGMP in the presence and absence of calmodulin. They concluded that Phospholipase A 2 is a finely regulated enzyme controlled directly by a host of key intracellular regulators. 

Involvement of inositide metabolism in the transduction mechanism from receptor activation to control of cellular processes such as contraction 

What Determines the Nature of the Eicosanoids Produced by Individual 

Once released, it is believed that the unesterified arachidonic acid could serve as substrate for oxygenation by both cyclooxygenase and lipoxygenase pathways. However the cellular location of the enzymes is different. 

The explanations for all these different responses are unknown, but clearly a better understanding of factors modulating eicosanoid production is of fundamental importance. 

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