The anterior pituitary gland, a diminutive yet physiologically pivotal endocrine organ, regulates various bodily functions in order to maintain the hormonal equilibrium within the body. It is situated at the base of the brain in the Sella turcica, originating embryologically from Rathke’s pouch, an ectodermal outgrowth of the oral cavity. Its six hormones are secreted by distinct cell clusters under the control of the hypothalamus. These hormones are often referred to as ‘tropins,’ which stimulate the synthesis and secretion of hormones released by other endocrine glands. Five distinct cell types have been identified in the anterior pituitary: corticotrophs, lactotrophs, thyrotrophs, gonadotrophs, and somatotrophs, responsible for secreting ACTH, PRL, TSH, LH/FSH, and GH, respectively. The secretion of tropic hormones is regulated by a dual-control mechanism involving negative feedback inhibition and positive stimulation by hypothalamic-releasing factors. Excessive release of these hormones can lead to a variety of disorders impacting growth, metabolism, reproductive processes, and physiology as a whole.
Anterior pituitary, Hypothalamus, Tropins, Feedback
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