Endocrine Regulatory Axes
Fundamentals of Endocrinology and Hormones
Endocrine Regulatory Axes
Endocrine regulatory axes are linked pathways connecting controlling signals, hormone-producing glands and responding tissues. The hypothalamic–pituitary–thyroid, adrenal and gonadal axes are common examples of hierarchical organization.
Direction of communication
A hypothalamic factor modifies pituitary secretion. A pituitary trophic hormone then influences a peripheral gland. The peripheral product feeds back to central sites, while local and environmental inputs modify several levels.
Axes differ
Prolactin is strongly regulated by tonic dopamine inhibition rather than a simple three-gland stimulatory chain. Insulin and parathyroid hormone are closely controlled by circulating nutrients or ions. Not every endocrine system fits the same schematic.
Reading paired results
A peripheral hormone should often be considered alongside its controlling hormone. This helps distinguish a primary gland problem from a central disturbance. In athletes, low energy availability may suppress reproductive regulation without implying that the gonads alone initiated the change.
Home
Academy
Site Map