What is the primary physiological effect of corticosteroids blocking Phospholipase A2?

Corticosteroids exert their physiological effects primarily by inhibiting the enzyme phospholipase A2. This enzyme is crucial in the inflammatory response because it catalyzes the release of arachidonic acid from membrane phospholipids. Arachidonic acid serves as a precursor for various inflammatory mediators, including prostaglandins and leukotrienes.

By blocking phospholipase A2, corticosteroids lead to a decrease in the production of arachidonic acid, consequently resulting in a significant reduction in the synthesis of prostaglandins. Prostaglandins play key roles in promoting inflammation, pain, and fever. Therefore, when their production is reduced, it leads to an overall dampening of the inflammatory process. This is a central mechanism through which corticosteroids exert their anti-inflammatory effects.

In summary, the primary physiological effect of corticosteroids acting through the inhibition of phospholipase A2 is the decreased production of prostaglandins, which in turn reduces inflammation and related symptoms.