Adenohypophysis: what it is, functions and hormones that secretes
Our body is made up of a large number of different structures, which in turn are made up of millions of cells. In this great framework, we can find that there are a series of chemical substances secreted by the organism and whose action regulates our behavior and allows phenomena such as growth, sexual behavior or the search for food. It is about the hormones, which circulate through the endocrine system, in which we can find different structures, some of them at the brain level.
In this sense the pituitary gland stands out, which in turn can be divided into several substructures. One of them, which we are going to talk about throughout this article, is the adenohypophysis .
- Related article: "Pituitary gland (hypophysis): the nexus between neurons and hormones"
Adenohypophysis: definition and main functions
It receives the name of adenohypophysis a the anterior and larger portion of the pituitary or pituitary gland . This ovoid structure is located in the basal part of the brain, below the hypothalamus (with which it is connected by the pituitary stalk) and resting in the hollow of the sphenoid bone known as the sella turcica.
It is a small brain region of great importance for our development as human beings, its main function being to regulate the emission of a large amount of hormones. It is therefore part of the neuroendocrine system, and in particular it is linked to hormones related to growth, metabolism and sexuality .
This brain region is highly vascularized, and has a large number of glandular cells . In this sense the adenohypophysis is made up of six major cell types, of which at least five are known to release the different hormones that the adenohypophysis secretes and regulates: somatotropes (that release the growth hormone), mamótrapas (that influence the release of prolactin and thyrotropin), corticotropins (secrete corticotropin or ACTH), gonadotropins (linked to sex hormones, in this case follicle-stimulating and luteal hormone), thyrotropic (stimulate prolactin synthesis, but especially thyrotropin) and chromophobic (which is believed to serve to renew the possible loss of the previous ones).
- Related article: "Parts of the human brain (and functions)"
Hormones that governs this structure
The anterior pituitary, as we have seen in the previous section, has the main function of secreting and regulating the levels of different hormones. These hormones are fundamental when generating and allowing different biological processes. Among the different hormones that it generates, the following stand out.
1. Corticotropin
Also known as adrenocorticotropic hormone, this substance is essential when generating endogenous glucocorticoids , mainly affecting the adrenal glands. Its action generates the stimulation of different hormones by said cortex, which allow regulating aspects such as metabolism (for example, it influences the secretion of insulin), homeostatic balance and inflammatory processes.
2. Betaendorfines
Beta-endorphins are other hormones released by the anterior pituitary gland. These are substances that act as endogenous opioids, usually associated with moderate, diminish or even inhibit the sensation of pain . In turn, it generates sensations of pleasure and relaxation. It is generated when making great efforts, or in pregnancy and childbirth.
3. Thyrotropin
Fundamental hormone that regulates the functioning of the thyroid, stimulating its action the secretion of thyroid hormones and the regulation of these in the body.
4. Prolactin
This hormone is essentially known to be responsible for generating milk production in the mammary glands after pregnancy (although the hormone itself already begins to raise its amounts during this). Apart from this action also influences the growth of the breasts, the inhibition of menstruation and the male refractory period.
5. Follicle-stimulating hormone
Essential substance in the field of reproduction, the follicle stimulating hormone exerts in women the role of stimulating the production of oocytes and estradiol (in men the same thing happens with the formation of sperm). Apart from that also has an effect on physical development and sexual maturation .
6. Luteinizing hormone
This hormone is deeply linked to reproduction and to the corpus luteum, one of its most known roles being that of generating the process of ovulation. In men, it also plays a role in reproduction and sexuality, since stimulates the production of testosterone by Leydig cells of the testicles.It also contributes to the genesis of progesterone, in such a way that the implantation of a possible fertilized ovum is facilitated.
7. Somatotropin or growth hormone
This hormone is fundamental, as its name suggests, for the stimulation of growth and physical development. Muscles and bones are affected by this hormone, among other structures. As well It is associated with the consumption and metabolism of fats and nutrients and its use in the body.
Alterations linked to this brain structure
The adenohypophysis is a fundamental structure for the human being, its alteration or injury can generate different disorders and consequences of varying severity.
In this sense it is possible to find that its dysfunction can generate alterations of growth, among which we can find both different types of dwarfism and gigantism (due to deficit or excess of growth hormone). The role of the adenohypophysis in the generation of thyroid hormones causes that its dysfunction is linked to the condition of both hypothyroidism (by default) and hyperthyroidism (by excess).
It can also affect reproductive function, affecting both libido (for example, hyperprolactinemia can occur) and the formation of hormones and sex cells. For example in the case of women could appear problems or even the cessation of menstruation and the ability to produce eggs. Finally, also can generate or affect metabolic disorders (including diabetes) and cause problems when metabolizing and using elements such as fats and carbohydrates.
