Why does thyroid hormone (TH) production often remain stable despite variations in thyrotropin-releasing hormone (TRH) from the hypothalamus?

💡 Explanation

TH levels are maintained by negative feedback, where increased TH inhibits both TRH release from the hypothalamus and TSH release from the anterior pituitary. This mechanism stabilizes TH production because even with TRH variations, the feedback loop adjusts TSH. Therefore, the thyroid remains stable, rather than being solely dictated by initial TRH levels.

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