Related Experiment Video
Updated: Aug 12, 2026

Frequent Tail-tip Blood Sampling in Mice for the Assessment of Pulsatile Luteinizing Hormone Secretion
Published on: July 4, 2018
Altered pulsatile and coordinate secretion of pituitary hormones in aging: evidence of feedback disruption
1Department of Internal Medicine, University of Virginia Health Sciences Center, Charlottesville 22908, USA.
Abstract:
A novel thesis is that healthy aging of neuroendocrine axes is marked by disruption of orderly patterns of hormone release. This can be quantified by a recently validated approximate entropy statistic applied to 24-hour hormone profiles, e.g., luteinizing hormone (LH), and growth hormone (GH). Moreover, more subtle disturbances of feedback control are indicated by decreased conditional regularity or synchrony (higher cross-approximate entropy) within coupled axes, such as ACTH-cortisol, LH-testosterone, etc. Such alterations can precede any changes in mean serum hormone concentrations, thus highlighting an impact of age on the feedback control mechanisms that coordinate the flow of signaling information within a neuroendocrine axis or network.
More Related Videos
Related Concept Videos
Feedback Loops
Regulation of Hormone Secretion
Humoral stimuli,...
Hormones of the Pituitary Gland
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...
Major Hormones and Their Functions
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
Aging
Cellular Clock Theory
The cellular clock theory posits that the human lifespan is closely tied to the finite capacity of cells to divide, a phenomenon governed by telomeres, which are protective caps at the ends of...
Cushing Syndrome II: Pathophysiology

