Gland
Zona fasciculata
The broad cortisol-producing cortical layer
High-yield
ACTH supports cortisol production, which varies in pulses and with circadian timing. In a usual daytime schedule, concentrations rise toward waking and fall toward the late evening.
Overview
In the middle adrenal cortex, lipid-rich cells form radial cords separated by sinusoids. This zona fasciculata is the major human cortisol-producing region. Its appearance reflects steroid synthesis and intracellular lipid stores.
Reference facts
- Location
- Between the outer glomerulosa and inner reticularis, forming the thickest cortical zone.
- Hormones
- Primarily cortisol, with smaller amounts of related steroid products.
- Blood supply
- Radial sinusoidal channels receive subcapsular arterial blood and carry it toward inner adrenal regions.
- Innervation
- Secretion is chiefly regulated through the ACTH axis, with local and neural influences on vascular and endocrine activity.
- Function
- Supports metabolic stress adaptation, vascular responsiveness and regulation of inflammatory and immune activity.
Clinical correlation
Sustained cortisol excess can cause central weight gain, proximal weakness, bruising, hypertension and impaired glucose tolerance. Prolonged external glucocorticoid exposure may suppress ACTH and reduce endogenous cortical activity; recovery varies among individuals.
Frequently asked questions
Where is the zona fasciculata located?
Between the outer glomerulosa and inner reticularis, forming the thickest cortical zone.
What does the zona fasciculata secrete?
Primarily cortisol, with smaller amounts of related steroid products.
What does the zona fasciculata do?
Supports metabolic stress adaptation, vascular responsiveness and regulation of inflammatory and immune activity.
What is the blood supply of the zona fasciculata?
The zona fasciculata is supplied by the radial sinusoidal channels receive subcapsular arterial blood and carry it toward inner adrenal regions.