If a drug inhibits phospholipase A2 in keratinocytes following ultraviolet (UV) exposure, which consequence follows regarding the skin's barrier function?

💡 Explanation

Inhibition of phospholipase A2 reduces the availability of arachidonic acid, a precursor to ceramides, which are critical lipids for the stratum corneum's barrier. The barrier function is weakened because decreased ceramide synthesis compromises the intercellular lipid lamellae, therefore increasing permeability, rather than accelerating collagen degradation.

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