hypophyseal


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pituitary

 [pĭ-tu´ĭ-tar″e]
1. pertaining to the pituitary gland.
3. a preparation of the pituitary glands of animals, used therapeutically.
pituitary gland an endocrine gland located at the base of the brain in a small recess of the sphenoid bone called the sella turcica. It is attached by the hypophyseal stalk to the hypothalamus and is divided into an anterior lobe (the adenohypophysis) and a posterior lobe (the neurohypophysis), which differ in embryological function and origin. Called also hypophysis.

The adenohypophysis originates from epithelial tissue. The adenohypophysis secretes six important hormones: growth hormone, thyroid-stimulating hormone or thyrotropin, adrenocorticotropic hormone or corticotropin, prolactin, follicle-stimulating hormone, and luteinizing hormone. Most of these hormones are tropic hormones, which regulate the growth, development, and proper functioning of other endocrine glands and are of vital importance to the growth, maturation, and reproduction of the individual. Secretion of the anterior pituitary hormones is controlled by releasing and inhibiting hormones produced by the hypothalamus. Information gathered by the nervous system about the well-being of an individual is collected in the hypothalamus and used to control the secretion of hormones by the pituitary gland. The hypothalamic releasing and inhibiting hormones are transported to the pituitary gland by way of the hypothalamic-hypophyseal portal system in which the hypothalamic venules connect with the capillaries of the anterior pituitary.

The neurohypophysis originates from neural tissue; it stores and secretes two hormones, oxytocin and vasopressin (antidiuretic hormone). These hormones are synthesized in the cell bodies of neurons located in the hypothalamus and transported along the axons to the terminals located in the neurohypophysis and are released in response to neural stimulation.

Surgical removal of part or all of the pituitary gland is called hypophysectomy and is usually done for treatment of a pituitary tumor. Because of its influence on the adrenal cortex and other endocrine glands, removal of the pituitary gland has widespread effects on the body. See hypophysectomy.
The pituitary gland and its relationship to the hypothalamus.
posterior pituitary neurohypophysis.

hy·po·phy·si·al

(hī'pō-fiz'ē-ăl),
Relating to a hypophysis.
Synonym(s): hypophyseal
References in periodicals archive ?
Karsch, "Systemic challenge with endotoxin stimulates corticotropin-releasing hormone and arginine vasopressin secretion into hypophyseal portal blood: coincidence with gonadotropin-releasing hormone suppression," Endocrinology, vol.
Cockram, "Adrenal and hypophyseal non-Hodgkin's lymphoma presenting with panhypopituitarism," International Journal of Clinical Practice, vol.
This data suggests that the suppressive effect of immune stress on GnRH release to the hypophyseal portal blood previously described in sheep [36] could result from reduced GnRH gene expression in the POA.
Bailey, "A consideration of the hypophyseal adenomata," British Journal of Surgery, vol.
Hypophyseal hemorrhage and panhypopituitarism during Puumala virus infection: magnetic resonance imaging and detection of viral antigen in the hypophysis.
This may be due to the fact that the blood supply of the posterior lobe originates from the hypophyseal artery, whereas the anterior lobe is supplied by the portal vessels resulting in a less direct pathway for hematogenous spread.
Hypophyseal tuberculoma: direct radiosurgery is contraindicated for a lesion with a thickened pituitary stalk: case report.
In diurnally active persons, CRH is released into the hypophyseal portal vein in the form of pulsatile bursts but in a circadian fashion, resulting in ACTH being secreted in an identical temporal pattern, with the amplitude and frequency of ACTH pulses being highest during the late night and morning hours (Fig.
However, in male-oriented rams, it appears that LH secretion pattern is indistinguishable from that of female-oriented rams and that both are defeminized compared to ewes, suggesting that sexual attraction is not related to organizational differences in the hypophyseal portal system (Stormshak, Estill, Resko, & Roselli, 2008).
This decapeptide is synthesized and released by hypothalamic secretory neuron which is delivered to the pituitary gland via hypophyseal portal blood system.