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T4 T3 Regulation

Meaning

T4 T3 Regulation describes the complex, multi-step process governing the synthesis, secretion, transport, and peripheral conversion of the two primary thyroid hormones, Thyroxine (T4) and Triiodothyronine (T3). T4 is the prohormone, and T3 is the metabolically active form, meaning efficient conversion of T4 to T3 in peripheral tissues is essential for systemic metabolic function. Proper regulation is critical because thyroid hormones impact nearly every cell in the body, influencing energy expenditure, body temperature, and protein synthesis. Clinical assessment requires a nuanced view of this entire regulatory cascade.