Macroprolactinum - what is it? Macroprolactin assay: normal and abnormal

Prolactin (luteotropic) is called a hormone produced by adenohypophysis cells. The substance has several forms, in the form of which it is in the human body. One of these forms of luteotropic hormone is macro-prolactin. What is it, what are its functions and properties, we will consider further.

Basic concepts of prolactin

The hormone consists of their prolactin-like proteins and is considered a peptide substance. Its property is based on participation in the processes of reproduction, and the organs that are the targets of action are the mammary glands.

Receptors that react to prolactin have been found in other parts of the body, but it is still unclear how they respond to the effect of the hormonal substance. Sensitive receptors are found in the following organs:

• spleen;
• lungs;
• Thymus;
• a heart;
• pancreas;
• Kidney;
• Uterus and ovaries;
• Skin integument.

The hormone exists in human blood in three forms: 85% of the substance has the form of a monomer, 10% - a kind of dimer and only 5% are in the form of macroprolactin.

Prolactin functions

The main "task" of the hormone is to increase and maintain a sufficient level of milk production during the child's breast-feeding. In pregnancy, a sufficient level of prolactin is maintained by the sex hormones estrogens. After the birth of the baby, the amount of estrogens decreases sharply.

During this period, the development of prolactin is supported by stimulation of the nipple mechanoreceptors. The baby with his active breast sucking provokes the release of oxytocin, which contributes to the allocation of milk. That is, prolactin stimulates the production of milk and its accumulation in the breast, but oxytocin is responsible for the process of milk allocation.

The action of prolactin during pregnancy can be visually seen on a newborn. The high content of the hormone leaves an imprint on the baby. A few days after birth from the baby's breast, there may also be milk allocation, which does not require additional intervention and independently pass during the first week of life.

Other properties of the luteotropic hormone:

• Inhibition of ovulation;
• Prolongation of the period of existence of the yellow body;
• Prevention of a new pregnancy;
• A small analgesic effect;
• Participation in the formation of surfactant;
• Ensuring immune tolerance of the embryo;
• Participation in the provision of orgasm.

Mechanism of pathology development

In the body of a healthy man and a non-pregnant woman who does not have health problems, the production of prolactin is inhibited by the active substance dopamine. It is synthesized in the hypothalamus. With any pathological conditions, there is a disruption in the relationship between the pituitary and the hypothalamus, as a result of which adenohypophysis cells synthesize luteotropic hormone and its level increases in serum.

Macroprolactinum - what is it?

It is a form of prolactin, which has a high molecular weight. It exists in the body in small quantities. The peculiarity of the form is the connection of a hormonal active substance with an immunoglobulin.

Prolactin and macroprolactin in an amount above the norm should be present only in the body of a pregnant and lactating woman. All other cases are considered pathological.

Macroprolactin, which has a higher molecular mass, is inherent in accumulating in the body. Other forms of luteotropic hormone are derived faster because of low molecular weight.

Macroprolactin, the norm of which will be considered below, has little biological activity, which means that the organism can not react to slight changes in its indices. The clinical picture is poorly expressed or accompanied by violations of the menstrual cycle, which is not a specific indicator of pathology.

The male also synthesizes this hormone. He is responsible for the production of spermatozoa, their activity and the synthesis of testosterone. In men, the indices of macroprolactin are much lower than in women.

The analysis for the study of hormone levels, as well as its qualitative and quantitative characteristics are prescribed in the case of long infertility with diagnostic purposes.

Hypermaproperactinemia

If the macroprolactin is elevated, then this condition is called hypermacroprolactinemia. This pathology is not a provoking factor in the development of malignant breasts and osteoporosis in comparison with the state of increasing the amount of usual prolactin.

It should be remembered that a sharp rise in the level of hormone in unkrafts indicates a disturbance in the work of the hypothalamic-pituitary system. The presence of a significant amount of macroprolactin can manifest itself in the form of dysmenorrhea, and sometimes even cause infertility.

Prolactinoma

The term "prolactinoma" refers to benign pituitary formation, a feature of which is the production of luteotropic hormone. Adenomas can occur both in women and in men. The etiology of the appearance of prolactinoma has not yet been elucidated. There are opinions about hereditary predisposition, and also that tumors appear in parallel with pathologies of other organs of the endocrine system.

Classify two types of tumors by their size and location:

• Intrasellar shells do not extend beyond the Turkish saddle and have a diameter of less than 10 mm;
• Extrasellar extend beyond the Turkish saddle and have a diameter greater than 10 mm.

In addition to the main syndromes and manifestations, against which specialists prescribe diagnostics for prolactin and macroprolactin, there are a number of other clinical signs of the disease:

• Narrowing of visual fields;
• Sharp decrease in visual acuity;
• Bifurcation in the eyes;
• Impossibility to use lateral vision;
• headache;
• depression;
• Anxiety and irritability;
• In severe cases, complete blindness.

In addition to laboratory diagnosis, CT and MRI of the brain, stimulation (hormonal) and densitometry (assessment of bone density used for differentiation) are used to make a correct diagnosis.

Diagnostic Features

The analysis on macropolylactin - what is it? This diagnostic method of immunochemiluminescent reaction, which is prescribed to all patients with elevated levels of prolactin in the body.

Analysis is one of the innovative methods. When it is carried out, the molecules of the hormone are "populated" by luminescent particles, which, when bound to prolactin, illuminate the areas under the action of ultraviolet radiation. The level of luminescence is measured by luminometers - special portable devices.

The quantitative indices of macroprolactin are determined with the help of polyethylene glycol. They carry out the precipitation of immune complexes. If after this process, less than 40% of the total luteotropic hormone level is determined in the serum , this is an indication that there is a significant amount of macroprolactin in the material under study.

Indications for diagnosis

There are a number of conditions in which specialists assign a definition of the qualitative and quantitative indices of prolactin and its forms. The analysis for macroprolactin is carried out in the following cases:

• Galactorrhea - pathological secretion of milk or colostrum;
• The presence of prolactin - adenohypophysis tumors that synthesize an excessive amount of hormonal substance;
• Sharp deterioration of vision;
• infertility;
• Absence of menstruation for more than six months;
• Uterine bleeding of unexplained etiology;
• Study of pathology of the pituitary gland;
• Regular absence of ovulation;
• osteoporosis;
• Mastopathy;
• Evaluation of the effectiveness of prolactin therapy.

The norm of the indicators in different periods

The amount of detectable prolactin (results in μME / ml):

• Male norm - 44,5-375;
• The female norm is 59-619;
• Postmenopause - 38-430;
• Bearing of the child - 205,5-4420.

The results of the detection of macroprolactin are interpreted in such variants:

• A significant amount of macroprolactin;
• Macroprolactin is not detected;
• A significant amount of macroprolactin is in doubt.

Positive result

Hypermaproperactinemia is defined against the background of the following pathologies:

• Neoplasm of the hypothalamus;
• Tumor processes of the pituitary gland;
• Pathology of the thyroid gland (decrease in hormonal secretion);
• Polycystic ovary;
• Kidney failure;
• Liver disease;
• Adrenal gland anomalies , adrenal insufficiency ;
• Systemic lupus erythematosus;
• Arthritis of rheumatoid type;
• Hypovitaminosis of pyridoxine.

The significant presence of the amount of macroprolactin means also that the patient could take medication for a long time.

The hormonal level is affected by:

• Antihistamines;
• Antipsychotics;
• Diuretics;
• Antihypertensive drugs;
• Antipsychotic drugs;
• Oral contraceptives;
• Antidepressants;
• Antiemetic in large quantities and with prolonged use.

Decrease in values

With some states of macro-prolactin, the rate of which in women varies depending on the period of life, may be below the optimal parameters. This result is typical for the following cases:

• A pituitary infarction arising on the background of massive blood loss during labor;
• Pregnancy overdraft (more than 41-42 weeks);
• Long-term use of drugs to combat cramps, Calcitonin, hormones, Morphine, Rifampicin, Nifedipine.

Who appoints the study and where should it be handed in?

Several narrow specialists can direct the study: gynecologist, urologist or endocrinologist. The analysis is handled in laboratories of specialized medical clinics or family planning centers. Venous blood is needed for diagnosis.

In order for the results to be correct, the patient must be prepared for the analysis of macro-prolactin:

1. 12 hours before the change, give up food.
2. Several days before admission, do not use drugs based on estrogen and androgens. The specialist who gave the referral should inform the patient about it.
3. For 24 hours completely stop taking medications.
4. For several days before the analysis, exclude any physical activity and avoid stressful situations.
5. On the day of the test, you must stop smoking.

Conclusion

One of the forms of the luteotropic hormone is macroprolactin. What is it, what are the features of checking its qualitative and quantitative indicators - the necessary information for each couple who wants to become a future parent or is in the process of conception planning.