Why does prolonged inflammation in melanocyte-stimulating hormone (MSH)-sensitive skin regions result in hyperpigmentation, rather than hypopigmentation, even if the initial inflammatory trigger fades?

💡 Explanation

Prolonged inflammation sustains constitutive MSH receptor signaling, leading to continued melanin production even after the initial inflammatory trigger subsides, because the signaling pathway remains active. Therefore, hyperpigmentation occurs rather than hypopigmentation, because melanin production continues despite the absence of the original stimulus.

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