Somatostatin: characteristics and effects of this hormone

Somatostatin is a hormone and neurotransmitter with diverse effects in the human body.

Within the human body we can find a great quantity and variety of structures and organs that have different properties and functions. The main system in charge of this is the nervous system, but we must also highlight the important role of the endocrine system. the important role of the endocrine system.

In this sense, a large part of our body's functions depend on certain hormones altering or regulating the functioning of the organs, glands and tissues that are part of it. Y one of them is somatostatinof which we are going to speak throughout this article.

Somatostatin: what is it?

The somatostatin is one of the different hormones that our organism secretes naturally, which, like the rest of hormones, acts as a messenger that generates some type of alteration in the functioning or structure of other body systems.

We are dealing with a protein type substance that can be synthesized in two different forms, one of twenty-eight amino acids (with greater presence in the digestive tract) and another (the most common in the nervous system and pancreas, and the best known) formed by a total of fourteen amino acids, and which has an effect on different body systems such as the nervous, endocrine or even the digestive or excretory systems. It also acts as a neurotransmitter.

Somatostatin is a primarily inhibitory hormone, and its synthesis takes place in the pancreas. It is produced mainly in the islets of Langerhans, as are insulin and insulin-like hormones. like insulin and glucagon, specifically by the delta cells of these structures. However, we can also find other areas that synthesize and use it, among which the hypothalamus and other brain nuclei or even the walls of the gastrointestinal tract stand out.

Main functions of this hormone

Somatostatin is a hormone that can be found in most systems of our organism, and has different effects on it. As we have seen above it plays a mainly inhibitory role in most of the target organs..

One of the functions or properties for which it is best known is its inhibitory role of growth hormone, which allows growth to slow down to a large extent in adulthood and contribute to the regenerative capacity of our body by reducing the energy expenditure devoted to growth. To this end, it acts on the pituitary gland in such a way that it reduces the production of growth hormone or somatotropin. In fact, it is this function that has earned it the name somatotropin-releasing hormone inhibitor.

It also affects the release of other hormones, such as corticotropin, which allows the production of steroids by our adrenal glands. Also affects and inhibits the functioning and synthesis of thyroid hormones by suppressing their releasing factor.by suppressing its releasing factor in the pituitary gland. In addition, at the pancreatic level, somatostatin inhibits the release of insulin and glucagon, which controls the release of these hormones and can lead to an increase in Blood glucose levels.

In the digestive tract it inhibits and reduces intestinal motility and enzyme secretion, as well as the absorption of glucose and other nutrients. It also has an effect on the excretory system, reducing urination. Another of its effects is to reduce blood flow at the splenic or visceral level, as well as salivation or intestinal mucous membranes.

It also has an effect on the immune systemas well as on the cardiovascular system. In the nervous system it inhibits the functioning of part of the central system, as well as the autonomic system (in fact it reduces and hinders movement, having an effect on the extrapyramidal system). It also inhibits the release of monoamines such as noradrenaline and dopamine.

Pharmacological use: clinical utility

Somatostatin is as we have said a hormone present in our body, which originates mainly in the pancreas. However, some people may have some kind of deficit in its synthesis or be in a medical situation that may benefit from its external administration. Because of its effects on the body, somatostatin has also been synthesized in the laboratory. has also been synthesized in the laboratory to treat various conditions.

The synthetic somatostatin used as a drug is analogous and has the same chemical composition as the one produced by our body, and is applicable by infusion into the blood, by perfusion. It usually comes in the form of vials with lyophilized powder and ampoules with a solvent (usually sodium chloride) that allows its dissolution. The dosage in question will depend on various factors such as age or the presence of pathologies.

The use of this hormone is indicated for the treatment of internal hemorrhagesespecially with regard to injuries or ruptures of varicose veins and fistulas in areas such as esophagus or pancreas, or in the digestive tract.

The reason for this is that, as we have mentioned above, somatostatin inhibits not only hormones but also decreases the secretions of the digestive organs, intestinal motility and blood flow in the viscera. However, its use is only to complement other treatments, requiring other types of interventions to achieve clinical improvement.

In addition to this, it is the treatment of choice for acromegaly or gigantism due to its inhibition of the hormone due to its inhibition of growth hormone and pituitary activity. Another clinical application of this hormone is in pancreatic or gastric tumors, although in this case it acts more as a marker and as a vehicle for radioactive molecules that can fight against neoplasia, as well as in some pituitary tumors as an inhibitor of its activity.

Risks and side effects of its medical use

Somatostatin is a very useful hormone both naturally and in its clinical application. However, in the second case we may find that its use as a drug involves some risks. Sometimes it is contraindicated or smaller doses than usual have to be used.

Among the possible side effects, the following are relatively common hyperglycemia, dizziness and hot flushes, abdominal pain and nausea are relatively common.. Episodes of diarrhea, hypoglycemia, bradycardia and both hypo- and hypertension may also occur. Finally, there is a risk of arrhythmias, blockages and cardiac problems.

Also decreases the flow of urine and sodium in the blood, as well as glomerular filtration, something that can bewhich can be negative in people with severe renal problems. The presence of cardiac alterations in the early stages of treatment should be especially watched for, including monitoring of vital signs.

In terms of populations that should not take this drug, somatostatin is contraindicated in pregnant women or during childbirth or lactation (which should be suspended if treatment with this drug is essential) since it affects the growth hormone and this may cause alterations in the fetus or the baby. Its use in children or adolescents is not recommended.

Nor should it be mixed with other drugs unless the doctor so indicates, especially in the case of anxiolytics (which it potentiates). Obviously, this drug should not be taken by people who are allergic to somatostatin or any of the components of its preparation.

People with severe renal insufficiencyAlthough they can be treated with this drug, they should be treated with lower doses. Given that it blocks the release of insulin and glucagon and the risk of generating hyperglycemia, its pharmacological use should be especially controlled in diabetics, especially if they are insulin-dependent or type 1 (it may be necessary to administer insulin).

Bibliographic references

• Spanish Agency of Medicines and Health Products. (2011). Package leaflet: Information for the user. Somatostatin eumedica 250mcg. 1 Vial Lyophilized Powder+1 ampoule of solvent of 1 ml. Drug Information Center.
• Kandel, E.R.; Schwartz, J.H. & Jessell, T.M.. (2001). Principles of neuroscience. Fourth edition. McGraw-Hill Interamericana. Madrid.
• Ortega, E., Mestrón, A. and Webb, S.M. (2000). Utility of somatostatin analogues in gastroenteropancreatic neuroendocrine tumors and non-GH-producing pituitary tumors. Endorinology and Nutrition, 48 (5): 140-148.