Related Experiment Video
Updated: Aug 13, 2026
12:37
Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Interactions between the melanocortin system and the hypothalamo-pituitary-thyroid axis
Niamh M Martin1, Kirsty L Smith, Stephen R Bloom
1Department of Metabolic Medicine, Imperial College Faculty of Medicine at Hammersmith Campus, Du Cane Road, London W12 0NN, UK.
Peptides
|January 4, 2006
Summary
The hypothalamic melanocortin system, regulating feeding, interacts with the thyroid axis to control energy balance. This connection influences both energy intake and expenditure for homeostasis.
Area of Science:
- Neuroendocrinology
- Metabolic Regulation
Background:
- Energy homeostasis relies on balancing energy intake and expenditure.
- The hypothalamic melanocortin system, involving alpha-MSH and AGRP, regulates feeding behavior through MC3-Rs and MC4-Rs.
Purpose of the Study:
- To review evidence for interactions between the melanocortin system and the hypothalamo-pituitary-thyroid (HPT) axis.
- To understand how this interaction impacts energy balance regulation.
Main Methods:
- Review of studies on transgenic mice and humans.
- Analysis of research on the melanocortin system and HPT axis.
Main Results:
- Compelling evidence shows the hypothalamic melanocortin system is crucial for energy balance.
- The melanocortin system interacts with the HPT axis, which regulates metabolism and energy expenditure.
Conclusions:
- The interplay between the melanocortin system and HPT axis offers a mechanism to control both energy intake and expenditure.
- Understanding these interactions is key to comprehending overall energy balance regulation.
Related Concept Videos
01:37Hypothalamic-Pituitary Axis
The response to stress—be it physical or psychological, acute or chronic—involves activation of the Hypothalamic-Pituitary-Adrenal (HPA) axis. The HPA axis is part of the neuroendocrine system because it involves both neuronal and hormonal communication. Its function is to regulate homeostatic systems—metabolic, cardiovascular, and immune—providing the necessary means to respond to a stressor.
01:20Synthesis and Regulation of Thyroid Hormones
Low blood levels of the thyroid hormones — triiodothyronine (T3) and thyroxine (T4) — signal the hypothalamus to release the thyrotropin-releasing hormone (TRH). TRH then reaches the pituitary gland and stimulates the release of thyroid-stimulating hormone(TSH) into the bloodstream.
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
Upon reaching the thyroid gland, TSH stimulates the follicular cells' active uptake of iodide ions from the blood. The ions diffuse to the apical surface of the cells and are oxidized to iodine. The iodine is then...
01:27Major Hormones and Their Functions
Hormones, the biochemical messengers produced by endocrine glands, are pivotal in regulating bodily functions and maintaining homeostasis. Each hormone's balance is crucial; imbalances can lead to significant physiological disruptions. Major hormones include oxytocin, cortisol, epinephrine, estrogen, testosterone, thyroxine, growth hormone, insulin, and glucagon.
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
Oxytocin, produced in the hypothalamus and released by the pituitary gland, plays a role in social bonding, childbirth, and lactation.
01:19Regulation of Hormone Secretion
Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction.
Humoral stimuli,...
Humoral stimuli,...
01:19Cushing Syndrome II: Pathophysiology
Cortisol production is normally governed by the hypothalamic–pituitary–adrenal (HPA) axis, which maintains hormonal balance through tightly regulated feedback mechanisms. Disruption of this regulatory system is central to the development of Cushing syndrome, whether the excess cortisol originates from external medications or internal pathology. Persistent cortisol elevation alters metabolism, immune function, and endocrine signaling, producing the characteristic clinical features of the...
01:23Hypothyroidism II: Pathophysiology
Hypothyroidism is a disorder characterized by insufficient production of thyroid hormones, which regulate metabolism, energy balance, and multiple organ systems.TypesHypothyroidism is classified based on the level of dysfunction. Primary hypothyroidism results from intrinsic thyroid gland dysfunction, causing reduced hormone production despite normal or increased stimulation. Secondary hypothyroidism arises from inadequate thyroid-stimulating hormone (TSH) secretion by the pituitary. Tertiary...