Growth hormone and somatostatin

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Growth hormone and somatostatin


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Growth hormone and somatostatin

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A 45-year-old man comes to the clinic because of a recent weight loss of 4.5-kg (9.9-lb) and recurrent fatty stools over the past several months. The patient has a history of diabetes mellitus and gallstones. Laboratory studies show decreased concentrations of pepsinogen, amylase, lipase, insulin, and glucagon. A CT scan shows a mass in the pancreas. Based on this patient's symptoms, which of the following substances might be secreted by this pancreatic tumor?  

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Acromegaly p. 345

somatostatin analogs for p. 335

somatostatin for p. 362

Carcinoid syndrome p. 356, 592

somatostatin for p. 362

Δ cells

somatostatinomas of p. 357

somatostatin production p. 380

Glucagon p. 335

somatostatin and p. 380

somatostatinomas and p. 357

Glucagonomas p. 358

somatostatin for p. 364

Growth hormone (GH) p. 340, 364

somatostatin p. 343

Insulin p. 335

somatostatin and p. 380

somatostatinomas and p. 357


somatostatin and p. 380


glucagon and p. 335

hypothalamic/pituitary drugs p. 364

hypothalamic-pituitary hormones p. 334

production of p. 337

regulatory substances p. 380

secretory cell locations p. 382


Growth hormone, also known as somatotropin, is a hormone which helps regulate the rate of growth in the body.

Secretion of growth hormone is dependent on the hypothalamic-pituitary axis.

The hypothalamus, which is a part of the brain, secretes growth hormone-releasing hormone into the hypophyseal portal system - which is a network of capillaries linking the hypothalamus to the anterior, or front part of the pituitary gland.

In the anterior pituitary, there are many different types of cells, each responsible for producing a type of hormone.

The growth hormone-releasing hormone binds to a surface protein on one of these cells, called somatotroph cells, and stimulates them to release of growth hormone.

Normally, growth hormone releasing hormone is released in a pulsatile manner, throughout the day and peaks one hour after you fall asleep, but it is also secreted in response to various forms of internal and external stimuli.

For example, the hypothalamus senses when there’s hypoglycemia, or low blood sugar, and in response it secretes growth hormone releasing hormone.

Exercise causes the adrenal glands to secrete epinephrine and that stimulates the hypothalamus to secrete growth hormone releasing hormone as well.

Also, during puberty, increased levels of estrogen and testosterone stimulate the hypothalamus to release growth hormone releasing hormone, which is responsible for the growth spurt.


Growth hormone (GH) is a peptide hormone that stimulates growth, cell reproduction, and regeneration. It is also known as somatotropin and is released by the anterior pituitary gland. Somatostatin is a peptide hormone produced by the hypothalamus. It inhibits the release of GH from the anterior pituitary gland and the secretion of insulin and glucagon from the pancreas, and also reduces gastrointestinal motility.


  1. "Medical Physiology" Elsevier (2016)
  2. "Physiology" Elsevier (2017)
  3. "Human Anatomy & Physiology" Pearson (2018)
  4. "Principles of Anatomy and Physiology" Wiley (2014)
  5. "Growth hormone secretion during sleep" Journal of Clinical Investigation (1968)
  6. "Growth hormone pulsatility profile characteristics following acute heavy resistance exercise" Journal of Applied Physiology (2001)

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