What Is the Relationship Between the Hypothalamus and Pituitary Gland?

A complete neuroendocrine system consisting of the hypothalamus and the pituitary gland. This system can be divided into two parts: hypothalamus-adenohypophysis system. There is a neural and humoral connection between the two, that is, the peptide-stimulating neurons in the hypothalamic pituitary-stimulating region are transported to the pituitary gland via the pituitary portal system through the secreted peptide neurohormones (releasing hormones and releasing inhibitors). Secretion of pituitary hormones. Hypothalamus-Pituitary System. There is a direct neural connection. Peptide neurohormones secreted by neuroendocrine cells in the supraoptic and paraventricular nucleus of the hypothalamus can flow directly through the axon to the pituitary gland via the axonal flow and are stored here.

Hypothalamus-pituitary system

(Hypothalamus-pituitary system)

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hypothalamic-pituitary system

Hypothalamus-

Hypothalamus-Pituitary System

The pituitary gland is closely related to the hypothalamus in structure and function. The nerve fibers from the neurons in the supraoptic nucleus and paraventricular nucleus of the hypothalamus directly enter the neural pituitary, called the hypothalamic pituitary tract. Hormones synthesized and secreted by neurons in the supraoptic nucleus and paraventricular nucleus are transported along this bundle to the pituitary gland for storage, and then released into the blood circulation when needed.

Hormone and Physiological Function of Hypothalamus-Pituitary Gland Nervous

It is generally believed that the supraoptic nucleus may mainly produce antidiuretic hormone, while the paraventricular nucleus mainly produces oxytocin.

Antidiuretic hormone. Also called vasopressin. Its main physiological role is to promote the reabsorption of water molecules in the renal collecting duct and the distal tubule. Therefore, insufficient antidiuretic hormone secretion, excessive secretion, and abnormal response of the renal tubules against diuretic hormone can affect urine output. When the antidiuretic hormone is deficient, the daily urine output can be as much as ten liters, which is called diabetes insipidus.

Oxytocin. For pregnant uterus, oxytocin has a strong role in stimulating uterine muscle contraction, and it has a role in promoting breast milk excretion.

Regulation of neurohypophyseal hormone secretion in the hypothalamus-pituitary system

Antidiuretic hormone. Under physiological conditions, it is mainly regulated by changes in blood volume and extracellular fluid osmotic pressure.

Oxytocin. Stimulation of the external genitals, sucking of the nipples and stimulation of the uterus can cause the secretion of oxytocin, which is accompanied by contraction of the uterus, which can promote the movement of sperm to the fallopian tubes.