What is the Origin of Basal Growth Hormone Trough?

This concept is fundamental to clinical endocrinology, stemming from the detailed study of the pulsatile and circadian rhythm of growth hormone secretion. The "basal" aspect refers to the resting or non-stimulated state, while "trough" is a physiological term for the lowest point in a cyclical pattern of secretion. The necessity for this measurement technique arose from the inherent variability of single-point GH testing.

What is the Mechanism of Basal Growth Hormone Trough?

The trough level is largely determined by the interplay between somatostatin (GHIH) inhibition from the hypothalamus and the metabolic clearance rate of circulating GH. During these basal periods, the inhibitory somatostatin tone dominates the pituitary somatotroph cells, suppressing the release of stored hormone. A pathologically elevated basal trough can suggest excessive GH production, often seen in conditions like acromegaly, overriding the normal physiological feedback loops.

Basal Growth Hormone Trough ∞ Area

Basal Growth Hormone Trough

Meaning

This term refers to the lowest concentration of growth hormone (GH) observed in the systemic circulation during a pulsatile secretory profile, typically representing the nadir between distinct secretory bursts. Clinically, this specific measurement is crucial because it reflects the minimal non-stimulated GH output from the anterior pituitary gland. The basal trough serves as an important diagnostic benchmark, often indicating the degree of somatotropic axis function or suppression in a patient.