noun, plural: hypothalamic hormones
Any of the various neurohormones produced by specialized neurons in the hypothalamus and released from the axon terminals that protrude to the median eminence in order to reach and affect the anterior pituitary functions
The hypothalamic hormones refer to the various hormones produced by the specialized neurons in the hypothalamus. The hypothalamus is the region of the brain made up of several small nuclei. It is located between the thalamus and the midbrain. Since it produces hormones, it is considered as a part of the endocrine system (apart from the nervous system). The hormones that the hypothalamus produces control metabolism by exerting an influence on the function of the pituitary gland.
The hypothalamic hormones are neurohormones produced by specialized hypothalamic nuclei. Hypothalamic hormones act on the anterior pituitary gland, stimulating the latter to secrete hormones that regulate other endocrine glands and organs. (Because the hypothalamic hormones induce the release of another hormone from the anterior pituitary, they are also referred to as releasing hormones.
The hypothalamic hormones are produced by specialized neurons that have axon terminals that extend and form the bulk of the median eminence (as opposed to the neurohypohysial hormones released by axon terminals that extend to the neurohypophysis).
The axon terminals serve as the site of temporary storage of these hormones. As regards the median eminence, the hypothalamic hormones are released later into the hypophyseal portal system to reach the anterior pituitary to exert their effects. As regards the neurohypophysis (also called posterior pituitary), the axon terminal contains Herring bodies that store neurohypophysial hormones, oxytocin and vasopressin. The hypothalamus produces them but the hormones are released from the axon terminals that extend to the neurohypophysis (i.e. posterior pituitary).
Hypothalamic hormones are as follows:
- thryrotropin-releasing hormone
- corticotropin-releasing hormone
- growth hormone-releasing hormone
- gondadotropin-releasing hormone
The hormones produced by the hypothalamus are involved in various physiological processes. Some of these are thermoregulation, osmoregulation, blood sugar regulation, fat metabolism regulation, hunger and thirst regulation, sleeping patterns, circadian rhythms, etc.
- hypophysiotropic hormone
- releasing hormone