The hypothalamus is responsible, within the neuroendocrine system, for maintaining the body’s homeostasis. What are the characteristics of this important system? We will tell you.
The neuroendocrine system is responsible for producing and secreting hormones, which are chemical substances produced in the body, whose function is to regulate the activity of cells and organs. What else should we know about him?
This system is made up of neurons and glands, which are in charge of synthesizing the different hormones that control the body’s growth, metabolism, development and sexual function.
The glands of the neuroendocrine system secrete these substances into the blood in the necessary situations. It is through this fluid that they reach the different cells and trigger their functions.
Functions of the hormones of the neuroendocrine system
Hormones are the chemical messengers synthesized by the body. Therefore, they transfer information from one set of cells to another to coordinate the functions of different parts of the body. In addition to controlling many physiological functions, they are also involved in behavior.
As the publication “Physiology, Endocrine Hormones” highlights, the neuroendocrine system has numerous hormone-producing glands. However, the main ones are:
- Reproductive organs.
- Others: pancreas, pituitary gland.
On the other hand, the glands can be of two types: exocrine and endocrine. The former segregate their products through ducts. An example of the exocrine glands can be the digestive ones. As for the latter, they secrete hormones directly into the blood and come to act on the target organs or tissues.
Neuroendocrine system: the hypothalamus
The hypothalamus is located below the thalamus, which is just above the brain stem. Its main function is to maintain homeostasis, that is, the stability of the internal environment of the organism.
The hypothalamus links the nervous system with the neuroendocrine system through the pituitary gland. Its function is to secrete releasing hormones which cause other glands to secrete other hormones and to inhibit hormones that stimulate or inhibit the production of hormones in the anterior pituitary gland.
The neurosecretory cells of the hypothalamus produce antidiuretic hormone and oxytocin. These hormones are transported to the pituitary, which is where they are stored for later release.
Neuroendocrine system: the pituitary
The pituitary is located at the base of the brain. It is attached to the hypothalamus thanks to the median eminence. It is made up of two very different parts that work independently:
- Posterior hypophysis or neurohypophysis: it is considered an expansion of the hypothalamus whose main function is to store and release the hormones that come from it, which are oxytocin and vasopressin or antidiuretic hormone (ADH).
- Anterior pituitary or adenohypophysis: This part of the pituitary does not have any nerve connection. It acts as a kidney gland and secretes hormones that go to endocrine glands or tissues.
The main functions of oxytocin are related to reproduction. Mainly, it stimulates the secretion of milk by the breasts during lactation and promotes uterine contractions at the time of fertilization and delivery.
Antidiuretic hormone or ADH
This hormone causes the reabsorption of water in the kidneys. Therefore, urine output decreases. In addition, it contributes to homeostasis, since it regulates blood volume, electrolyte balance and blood pressure.
Neuroendocrine system: thyroid
When TSH hormone from the anterior pituitary reaches the thyroid gland, thyroid hormone is produced. Its main role is to regulate metabolic processes and especially the use of carbohydrates. In addition, it also influences growth and development, both body and nervous system.
When there is a deficit of these hormones in the neuroendocrine system, the person is said to suffer from hypothyroidism. In the opposite case, the disease is called hyperthyroidism.
Reproductive Organs: Sex Hormones
There are three sex hormones: androgens, estrogens, and progestogens. As for the former, their main functions are:
- Promote the development, growth and maintenance of the male reproductive organs.
- Promote the development of male secondary characters.
- Stimulate protein metabolism.
Estrogens, being female sex hormones, have effects similar to androgens. However, in women:
- They promote the development, growth and maintenance of the female reproductive organs.
- They promote the development of secondary female characters.
Lastly, progestogens. These hormones prepare the walls of the uterus for the implantation of the fertilized egg. Therefore, it is the protective hormone of labor. In addition, it prepares the breasts for the secretion of milk.
In short, the neuroendocrine system participates in almost all the processes that occur constantly inside the human body. Although many are unaware of its functions, its well-being is essential for the proper functioning of the body.