ENTRIES A–Z
Philip Winn in Dictionary of Biological Psychology, 2003
Hormones are chemical messengers which are synthesized in ENDOCRINE GLANDS, secreted into the circulatory system, and transported through the body in the blood to bind to RECEPTORS on target cells where they exert a specific physiological or biochemical regulatory action. The body has a number of endocrine glands which secrete one or more hormones. The PINEAL GLAND secretes MELATONIN. The posterior PITUITARY GLAND secretes OXYTOCIN and VASOPRESSIN. The anterior pituitary gland secretes GROWTH HORMONE, ADRENO CORTICOTROPIC HORMONE, THYROID-STIMULATING HORMONE, FOLLICLE-STIMULATING HORMONE, LUTEINIZING HORMONE and PROLACTIN. The intermediate pituitary synthesizes MELANOCYTE STIMULATING HORMONE and BETAENDORPHIN. There are nine hypopthalamic hormones which regulate the release of pituitary hormones: THYROTROPHIN-RELEASING HORMONE (also known as THYROID- STIMULATINGHORMONE-RELEASING HORMONE), CORTICOTROPIN RELEASING HORMONE, GONADOTROPHIN-RELEASING HORMONE (also known as LUTEINIZING-HORMONE-RELEASING HORMONE), GROWTH- HORMONE-RELEASING HORMONE, GROWTH-HORMONE-RELEASE- INHIBITING HORMONE (also known as SOMATOSTATIN), PROLACTIN- RELEASING FACTOR, PROLACTIN-INHIBITING FACTOR (which in fact may be the neurotransmitter DOPAMINE), MELANOCYTE STIMULATING HORMONE RELEASING FACTOR and MELANOCYTE STIMULATING HORMONE INHIBITING FACTOR (which may also turn out to be dopamine).
Head, neck and vertebral column
David Heylings, Stephen Carmichael, Samuel Leinster, Janak Saada, Bari M. Logan, Ralph T. Hutchings in McMinn’s Concise Human Anatomy, 2017
The hormones of the posterior pituitary - antidiuretic hormone (influencing urine production by the kidneys) and oxytocin (which stimulates uterine contraction and milk ejection from the breasts) - are produced by hypothalamic neurosecretory cells whose fibres store the secretion and run down the pituitary stalk. Although the anterior pituitary is also connected to the stalk, the factors that control it (produced by different hypothalamic cells) pass into a network of very small veins that surround the stalk - the hypophyseal portal system (like a miniature hepatic portal system) and so reach the anterior pituitary to deliver the stimuli for hormone production by its own cells. The main anterior pituitary hormones are growth hormones and those that control the thyroid and adrenal cortices, ovaries, testes, and breasts.
The endocrine system
Laurie K. McCorry, Martin M. Zdanowicz, Cynthia Y. Gonnella in Essentials of Human Physiology and Pathophysiology for Pharmacy and Allied Health, 2019
This chapter will consider the hormones secreted from several endocrine glands including the pituitary, thyroid, parathyroid, and adrenal glands, as well as the pancreas. It is important to note, however, that hormones may be secreted from organs and tissues whose primary functions are not endocrine in nature. For example, the hypothalamus synthesizes and releases many hormones that influence the secretion of hormones from the anterior pituitary gland. In addition, the hypothalamus synthesizes the hormones that are subsequently released from the posterior pituitary gland. Other tissues and their hormones include the following: Heart: atrial natriuretic hormone (Chapter 7)Kidneys: erythropoietin (Chapter 10)Stomach: gastrin (Chapter 9)Small intestine: secretin, cholecystokinin, gastric inhibitory peptide (Chapter 9)Gonads (ovaries and testes): estrogen, progesterone, testosterone (Chapter 12)
Correlations between clinical hormone change and pathological features of pituicytoma
Published in British Journal of Neurosurgery, 2018
Ting-Wei Chang, Ching-Yi Lee, Shih-Ming Jung, Hung-Yi Lai, Chun-Ting Chen, Mun-Chun Yeap, Chi-Cheng Chuang, Peng-Wei Hsu, Chen-Nen Chang, Po-Hsun Tu, Shih-Tseng Lee
Various neuroendocrine cells in the anterior pituitary gland are distributed differently.21,22 For instance, ACTH-secreting cells are located in the middle region, GH-secreting cells are located in the lateral region, PRL-secreting cells are in the posterior-lateral region, and TSH-secreting cells are in the anterior region23 (Figure 7). As illustrated in Figure 7, in our patients, two tumours were located in the PRL-secreting cell region, correlating with PRL secretion changes; one was located in the GH-secreting cell region, correlating with acromegaly; and two were located in the ACTH-secreting cell region, correlating with Cushing disease. Among these patients, only one presented with hyposecretory activity; the remaining five patients presented with hypersecretory activity. These image correlations confirm that pituicytoma induces hyperactivity in pituitary gland cells with certainty.
Safety of current recombinant human growth hormone treatments for adults with growth hormone deficiency and unmet needs
Published in Expert Opinion on Drug Safety, 2020
Charlotte Höybye, Paolo Beck-Peccoz, Suat Simsek, Markus Zabransky, Hichem Zouater, Günter Stalla, Robert D Murray
To understand the potential effects, adverse effects, and risks of GH replacement some knowledge of physiology is useful. Serum GH is heterogeneous, consisting of two major forms, the predominant isomer being a 22-KDa peptide consisting of 191 amino acids and four α-helices, and a 20-KDa spliced variant lacking an internal sequence of 15 amino acids, which accounts for around 10% of total GH secretion [4]. It is synthesized and released from the anterior pituitary gland. GH secretion is induced by ghrelin and hypothalamic GHRH (Growth Hormone Releasing Hormone) and inhibited by somatostatin in addition to negative feedback by insulin-like growth factor I (IGF-I) [5]. GH has a half-life of 10–20 minutes and is secreted in pulses throughout the day, with an increased number of pulses during sleep. The release of GH is affected by many different factors, among them age, gender, nutrition, and illness [5]. The largest GH bursts are seen in puberty and the bursts are higher in women than in men. GH increases the production of IGF-I.
Non-adenomatous pituitary tumours mimicking functioning pituitary adenomas
Published in British Journal of Neurosurgery, 2020
Zize Feng, Zhigang Mao, Zongming Wang, Bing Liao, Yonghong Zhu, Haijun Wang
In contrast to these cases, several cases of pituicytomas or GCTs without accompanying hyperplasia or adenoma have been reported. In 2013, Chakraborti et al.18 reported a case involving symptomatic corticotropin hypersecretion. The patient underwent an endoscopic transsphenoidal procedure and excision of the tumour. The pathological analysis results revealed a pituicytoma. Postoperative serum ACTH hormone and cortisol levels decreased to normal, and the symptoms resolved. Losa et al.14 reported a case that presented with acromegaly linked to a neurohypophyseal GCT in 2000. Clinical and biochemical remission was achieved after the lesion was removed. The anterior pituitary hormones and GH-releasing hormone (GHRH) of the specimen were proved negative by histological analysis. In our study, one and two cases presented with Cushing’s syndrome and acromegaly, respectively. Two of them achieved remission following total tumour resection, while in one case the tumour was only partially resected. Postoperative histological examination confirmed the diagnosis of pituicytoma or GCT. In all specimens from the three cases, anterior pituitary hormones were undetectable in the immunohistological staining analysis, and no adenomatous evidence was found.
Related Knowledge Centers
- Lactation
- Physiology
- Stress
- Endocrine System
- Posterior Pituitary
- Pituitary Gland
- Gland
- Development of The Human Body
- Reproduction
- Blood Test