Hypothalamic-pituitary system

The hypothalamic-pituitary system is a structural morphofunctional association of the pituitary (appendage, lower appendage of the brain) and hypothalamus (a division in the intermediate brain) that participate in the regulation of the main vegetative functions in the body.

The hormones produced in the department of the intermediate brain have a direct inhibitory or stimulating effect on the secretion of the hormones of the lower cerebral appendage. The hypothalamic-pituitary system also has a feedback function. With its help, regulation of secretion and synthesis of hormones is carried out (with the increase in hormone production in the glands of internal secretion, the secretion of hormones in the department of the intermediate brain decreases). Hypothalamic-pituitary system, testing feedback, helps maintain the body's consistency.

Hypophisotropic hormones of the intermediate brain are divided into liberins (strengthening) and statins (inhibitory) production of the corresponding tropic hormones. In the department of the intermediate brain, neuropeptides are produced (a kind of protein molecules).

For most of the pituitary hormones, the hypothalamus has a stimulating effect, in contrast to the production of prolactin - the secretion is under the inhibitory tonic effect of the hypothalamus.

If the lesion (low cut) is damaged in the leg of the lower medullary appendage, the secretion of oxytocin and vasopressin by axons remains in the middle elevation. Thus, diabetes insipidus does not develop. Removal of the hypothalamus or high cutting of the legs provokes the loss of production of oxytocin, vasopressin and all, except prolactin, hormones in the pituitary.

Thus, the hypothalamic-pituitary system functions.

Physiology involves the implementation of interrelation through portal vessels in the adenohypophysis. Vascular walls are permeable to large proteins. Groups of cells in the hypothalamus form separate nuclei. Among them are 32 pairs. They take part in the regulation of the most important functions in the body. In this area, the higher centers of the parasympathetic and sympathetic divisions are concentrated in the nervous vegetative system. Thus, regulation of arterial pressure, heat transfer, sleep, heat production, appetite, vascular permeability and other things is carried out.

The hypothalamic-pituitary system is involved not only in maintaining a constant in the internal environment of a person. It also provides monthly, diurnal, seasonal and other rhythmic hormonal fluctuations.

The GGNS (hypothalamic-pituitary-adrenal system) is able to exert a significant inhibitory effect on the functioning of the female reproductive system at various levels. Proiopomelanocortin peptides produced by corticoliberin (KTG-corticotropin-releasing hormone) exert a suppressive effect on the production of the gondotrope-releasing hormone hypothalamus. Glucocorticoids inhibit the production of LH (luteinizing hormone) of the pituitary and progesterone and estrogens in the ovaries, reduce the sensitivity of different tissues to estradiol.

Thus, the key role of the GGNS in the formation of stress amenorrhea (absence of menstruation in the period of more than 6 months) is "hypothalamic". Along with this, there is a direct stimulating effect of estrogen on the gene promoter (the previous nucleotide sequence), which is responsible for the synthesis of CRH, as well as noradrenergic structures in the CNS. This explains the presence of moderate hypercorticism (increased functionality of the adrenal cortex), anxiety, affective disorders, mood swings, impaired appetite and other symptoms.