Endocrine physiology 1/

Question 1

Why may a patient have dark/pigmented skin in primary adrenal insufficiency?

Answer 1

• In primary adrenal insufficiency, hypothalamus works more to produce ACTH (as a negative feedback mech of low cortisol in blood, to compensate)
• Since ACTH and MSH share the same precursor for synthesis in ant. pit., increase in ACTH production simultaneously increases MSH production
• lead to dark skin