29. Physiology - Growth Hormone

<p>191 (A)</p> Signup and view all the answers

<p>In small-bodied neurons of the arcuate nucleus of the hypothalamus. (A)</p> Signup and view all the answers

<p>Granules (D)</p> Signup and view all the answers

<p>By increasing intracellular cAMP and calcium concentrations. (C)</p> Signup and view all the answers

<p>Pre 22.5-kDa growth hormone mRNA (C)</p> Signup and view all the answers

<p>A 14-amino acid neuropeptide. (B)</p> Signup and view all the answers

<p>Growth hormone (GH) and insulin-like growth factor 1 (IGF-1) (B)</p> Signup and view all the answers

<p>2 (A)</p> Signup and view all the answers

<p>Through the long portal veins. (B)</p> Signup and view all the answers

<p>Somatotrophic cells in the anterior pituitary (B)</p> Signup and view all the answers

<p>Alternative splicing of mRNA (C)</p> Signup and view all the answers

<p>Five (D)</p> Signup and view all the answers

<p>Insulin (A)</p> Signup and view all the answers

<p>It contains 191 amino acids. (A)</p> Signup and view all the answers

<p>Chromosome 17 (B)</p> Signup and view all the answers

<p>Placental chorionic somatomammotropins (D)</p> Signup and view all the answers

<p>Golgi apparatus (B)</p> Signup and view all the answers

<p>Removal of a specific segment of RNA (A)</p> Signup and view all the answers

<p>To inhibit GH release by binding to receptors on somatotroph cells. (A)</p> Signup and view all the answers

<p>Activation of adenylate cyclase (AC) via a G-protein. (B)</p> Signup and view all the answers

<p>It activates protein kinase A (PKA), which promotes GH synthesis and release. (D)</p> Signup and view all the answers

<p>By inhibiting the activity of adenylate cyclase (AC), which decreases cAMP levels. (C)</p> Signup and view all the answers

<p>Adenylate cyclase (AC). (A)</p> Signup and view all the answers

<p>Stimulation of growth hormone (GH) synthesis and release. (B)</p> Signup and view all the answers

<p>An inhibitory G-protein that reduces cAMP levels. (B)</p> Signup and view all the answers

<p>Protein kinase A (PKA). (B)</p> Signup and view all the answers

<p>Decreased release of GH as cAMP production would be inhibited. (B)</p> Signup and view all the answers

<p>Promotion of GH synthesis and release. (C)</p> Signup and view all the answers

<p>Arcuate nucleus (C)</p> Signup and view all the answers

<p>To inhibit GH secretion by reducing adenylate cyclase activity (B)</p> Signup and view all the answers

<p>cAMP/PKA signaling pathway (A)</p> Signup and view all the answers

<p>A potent inhibitor hormone (D)</p> Signup and view all the answers

<p>Through the hypophyseal portal blood supply (B)</p> Signup and view all the answers

<p>To decrease adenylate cyclase activity and, therefore, reduce GH secretion (A)</p> Signup and view all the answers

<p>It inhibits the cAMP/PKA pathway. (C)</p> Signup and view all the answers

<p>They have opposing effects on growth hormone secretion. (C)</p> Signup and view all the answers

<p>To promote the release and synthesis of growth hormone. (C)</p> Signup and view all the answers

<p>Somatostatin's inhibition of adenylate cyclase (C)</p> Signup and view all the answers

Growth hormone (GH) is a peptide hormone produced by the anterior pituitary gland, primarily by somatotroph cells.

Two splice variants of mRNA transcripts produce two forms of GH: 22.5-kDa (191 amino acids) and 20-kDa (176 amino acids). The 22.5-kDa version is the dominant form.

GH is synthesized by somatotroph cells in the pituitary gland. The gene is transcribed into mRNA, which is then translated into the protein.

Growth hormone releasing hormone (GHRH) is a hypothalamic hormone that stimulates GH release from the pituitary gland.

GH is stored in granules within somatotroph cells until stimulated to release by GHRH. This ensures efficient secretion when needed.

The synthesis and secretion of GH is regulated by a complex feedback loop involving GHRH, somatostatin, and IGF-1. This maintains appropriate GH levels.

GH's effects on growth are primarily mediated by insulin-like growth factor 1 (IGF-1), which is produced in response to GH action.

A family of biologically related proteins that include Growth Hormone (GH), placental lactogens, and prolactin.

Growth hormone (GH) is a member of the somatotropin/prolactin hormone family.

These hormones are produced by the placenta during pregnancy.

Also known as placental chorionic somatomammotropins.

A hormone that plays a role in breast development and milk production.

The process of producing two different forms of a protein from the same gene.

A specialized form of the endoplasmic reticulum (ER) involved in protein synthesis.

A cellular organelle that processes and packages proteins.

The site where growth hormone is synthesized and stored.

A hypothalamic hormone that stimulates the release of growth hormone (GH) from the anterior pituitary gland.

A hypothalamic hormone that inhibits the release of growth hormone (GH) from the anterior pituitary gland.

Specialized cells in the anterior pituitary gland responsible for producing and releasing growth hormone (GH).

GHRH binds to its receptor on somatotrophs, activating a signaling pathway that ultimately increases intracellular cAMP levels.

Somatostatin binds to its receptor on somatotrophs, initiating a signaling pathway that reduces intracellular cAMP levels, thus inhibiting GH release.

Growth hormone (GH) stimulates the production of insulin-like growth factor 1 (IGF-1), which plays a crucial role in promoting growth and development.

GH synthesis and release are tightly regulated by a feedback loop involving GHRH, somatostatin, and IGF-1.

The anterior pituitary gland releases GH, which stimulates the liver to produce IGF-1.

IGF-1 acts on various tissues, promoting growth and development, while also providing negative feedback to the hypothalamus and pituitary to regulate GH production.

GH levels fluctuate throughout the day, with peaks occurring during sleep, particularly during the first few hours of deep sleep.

Growth hormone (GH) is released from the pituitary in bursts throughout the day, not continuously.

GHRH, a hormone from the hypothalamus, stimulates the release of GH from the pituitary gland, while somatostatin inhibits it.

Growth hormone (GH) is synthesized by somatotroph cells in the pituitary gland. These cells store GH in granules and release it when stimulated by GHRH.

GHRH stimulates the somatotrophs to release GH by increasing intracellular cAMP and calcium levels.

Somatostatin, another hormone from the hypothalamus, inhibits the release of GH.

Growth hormone-releasing hormone (GHRH) is a 43-amino acid peptide produced by the hypothalamus that stimulates the release of growth hormone (GH) from the anterior pituitary gland.

GHRH reaches the somatotroph cells in the anterior pituitary gland via the hypophyseal portal blood supply.

Somatostatin is released by cells in the periventricular region of the hypothalamus into the hypophyseal portal blood supply.

The interaction between GHRH and somatostatin fine-tunes the release of growth hormone (GH), maintaining appropriate levels in the body.

The arcuate nucleus is a region in the hypothalamus that plays a role in regulating growth hormone (GH) release.

Both GHRH and somatostatin are released from specific regions within the hypothalamus, which then reach the anterior pituitary gland via the hypophyseal portal blood supply.

The release of growth hormone (GH) is a complex process involving a delicate balance between stimulatory (GHRH) and inhibitory (somatostatin) signals.