Adrenal Cortical Zonation
Adrenal Cortex and Corticosteroid Hormones
Adrenal Cortical Zonation
The adrenal cortex is organized into glomerulosa, fasciculata and reticularis zones with different enzyme expression and dominant secretory products. Their organization enables distinct regulation of mineralocorticoids, glucocorticoids and adrenal androgens.
Distinct adrenal pathways
Adrenal zones differ in enzyme expression and regulatory inputs. ACTH strongly influences glucocorticoid pathways, whereas angiotensin II and potassium are major aldosterone regulators. Steroid binding, local conversion and clearance modify the relationship between gland output and blood concentration.
Specific considerations
Zonation is functional as well as anatomical. Substrate availability and trophic signals interact with enzyme expression, so a shared cholesterol precursor does not imply identical regulation of all adrenal steroids.
Context for a result
Sampling time, illness, medicines, posture and sodium status matter differently for different adrenal tests. An exercise-associated rise is not itself a diagnosis. Persistent symptoms or abnormal biochemical patterns require the appropriate clinical assessment.
Home
Academy
Site Map