What is the Origin of Steroid Negative Feedback?

The concept is a core principle of endocrinology, combining "steroid," referring to the class of lipid-soluble hormones, with "negative feedback," a cybernetic term for a self-correcting regulatory loop. The discovery of the Hypothalamic-Pituitary-Adrenal (HPA) and Hypothalamic-Pituitary-Gonadal (HPG) axes provided the physiological basis for this model.

What is the Mechanism of Steroid Negative Feedback?

The mechanism involves steroid hormones diffusing into the cells of the hypothalamus and pituitary gland, where they bind to specific intracellular receptors. This binding event triggers a change in gene expression, leading to the suppression of the synthesis and release of the trophic hormones—such as GnRH, LH, and ACTH—that originally stimulated the steroid production. By dampening the signal at its source, the body effectively limits its own hormone output, returning the circulating levels to a set point.

Steroid Negative Feedback ∞ Area

Steroid Negative Feedback

Meaning

Steroid Negative Feedback is a fundamental endocrine regulatory mechanism where a high concentration of a circulating steroid hormone, such as cortisol or testosterone, inhibits the upstream release of its controlling pituitary and hypothalamic hormones. This self-regulating loop is essential for maintaining hormonal homeostasis, preventing excessive hormone secretion, and ensuring that the endocrine system operates within a tightly controlled physiological range. Disruption of this feedback mechanism can lead to conditions of hormone overproduction or deficiency.