Search results
Results from the WOW.Com Content Network
The anterior pituitary (also called the adenohypophysis or pars anterior) is a major organ of the endocrine system.The anterior pituitary is the glandular, anterior lobe that together with the posterior pituitary (or neurohypophysis) makes up the pituitary gland (hypophysis) which, in humans, is located at the base of the brain, protruding off the bottom of the hypothalamus.
The anterior pituitary is typically divided into two regions, a more anterior rostral portion and a posterior proximal portion, but the boundary between the two is often not clearly marked. In elasmobranchs, there is an additional, ventral lobe beneath the anterior pituitary proper. [27]
The cells of the anterior pituitary express specific G protein-coupled receptors that bind to the neuropeptides, activating intracellular second messenger cascades that produce the release of anterior pituitary hormones. [4] The following is a list of hormones that rely on the hypophyseal portal system to indirectly mediate their function by ...
Trophic hormones are hormones of the anterior lobe of the pituitary. These hormones affect growth, function, or nutrition of other endocrine cells. Trophic hormones can be found in body systems including the endocrine, gastrointestinal, urinary, and nervous systems.
Tropic hormones are hormones that have other endocrine glands as their target. Most tropic hormones are produced and secreted by the anterior pituitary. [1]: 719 The hypothalamus secretes tropic hormones that target the anterior pituitary, and the thyroid gland secretes thyroxine, which targets the hypothalamus and therefore can be considered a tropic hormone.
The pituitary gland is divided into three lobes: the anterior pituitary, the intermediate pituitary lobe, and the posterior pituitary. The hypothalamus controls the anterior pituitary's hormone secretion by sending releasing factors, called tropic hormones, down the hypothalamo-hypophysial portal system. [3]
The pituitary gland is located at the base of the brain, and intimately connected with the hypothalamus. It consists of two lobes: the posterior pituitary, which consists of nervous tissue branching out of the hypothalamus, and the anterior pituitary, which consists of hormone-producing epithelium.
Other hormone-secreting cells of the pituitary undergo rapid growth in pregnant women as well, which contribute to the gland's enlargement. [10] The anterior pituitary is supplied by a low pressure portal venous system. [15] The anterior pituitary is more commonly affected in Sheehan's syndrome because of the structure of the portal venous system.