Thyrotropin-stimulating hormone TSH

Thyrotropin stimulating hormone (TSH) Bovine pituitary Identification of thyroid cancer metastases in patients previously treated for thyroid cancer... 

Cortisol hypersecretion, blunted growth hormone and prolactin responses, blunted thyrotropin-stimulating hormone (TSH) response to TRH, reduced luteinizing hormone secretion, and disturbances in b-endorphin, vasopressin, and calcitonin have all been associated with depression. 

FSH Follicle-stimulating hormone TSH Thyrotropin-stimulating hormone... 

On the other hand, some receptors are truly promiscuous in that they can activate two or more G-proteins from quite different classes, even in their normal cellular environment. For example, similar concentrations of thyroid-stimulating hormone (TSH 0.1-100 U/ml) can stimulate the incorporation of 32P-GTP into a, aQ, a12, a13, as, and aq/11 through activation of the thyrotropin receptor in membranes from human thyroid gland. TRH activation of Ca2+ currents in GH3 cells is obtunded equally by antisense-depletion of l2, aa, and aq/11, but not of aQ. Some individual genotypic P2y nucleotide receptors can also couple with equal affinity to PTx-sensitive and PTx-insensitive G-proteins in sympathetic neurons. The degree, or otherwise, of such promiscuity is presumably determined by the structure of the receptor protein itself. 

A trophic hormone acts on another endocrine gland to stimulate secretion of its hormone. For example, thyrotropin, or thyroid-stimulating hormone (TSH), stimulates the secretion of thyroid hormones. Adrenocorticotropin, or adrenocorticotropic hormone (ACTH), stimulates the adrenal cortex to secrete the hormone cortisol. Both trophic hormones are produced by the pituitary gland in fact, many trophic hormones are secreted by the pituitary. The pituitary gland is sometimes referred to as the "master gland" because its hormones regulate the activity of other endocrine glands. 

Thyrotropin (thyroid-stimulating hormone, TSH) and the related hormones lutropin (luteinizing hormone, LH) and follitropin (follicle-stimulating hormone, FSH) originate in the adenohypophysis. They are all dimeric glycoproteins with masses of around 28 kDa. Thyrotropin stimulates the synthesis and secretion of thyroxin by the thyroid gland. 

The secretion of anterior pituitary hormones is controlled in part by hypothalamic regulatory factors that are stored in the hypothalamus and are released into the adenohypophyseal portal vasculature. Hypothalamic regulatory factors so far identified are peptides with the exception of dopamine. Secretion of anterior pituitary hormones is also controlled by factors produced more distally that circulate in the blood. Predominant control of hormone production may be relatively simple, as with thyroid-stimulating hormone (TSH), the production of which is primarily stimulated by thyrotropin-releasing hormone (TRH) and inhibited by thyroid hormones, or it may be complex, as with prolactin, the production of which is affected by many neurotransmitters and hormones. 

Secondary hypothyroidism, or pituitary hypothyroidism, is the consequence of impaired thyroid-stimulating hormone (TSH) secretion and is less common than primary hypothyroidism. It may result from any of the causes of hypopituitarism (e.g., pituitary tumor, postpartum pituitary necrosis, trauma). Patients with secondary hypothyroidism exhibit undetectable or inappropriately low serum TSH concentrations. In secondary hypothyroidism, a normal thyroid gland lacks the normal level of TSH stimulation necessary to synthesize and secrete thyroid hormones. Such patients usually also have impaired secretion of TSH in response to exogenous thyrotropin-releasing hormone (TRH) administration. 

Thyroid-stimulating hormone (TSH) Thyrotropin-releasing hormone (TRH)(+) Thyroid Thyroxine, triiodothyronine... 

Thyroid-stimulating hormone (TSH thyrotropin) In patients who have been treated surgically for thyroid carcinoma, to test for recurrence by assessing TSH-stimulated whole-body 131I scans and serum thyroglobulin determinations... 

Thyrotropin (thyroid-stimulating hormone, TSH)b Follitropin (follicle-stimulating hormone, FH)b Lutropin (luteinizing hormone, ICSH or LH)b Thyroid Ovaries, testes Ovaries, testes Ch 25, B2... 

Thyroid-stimulating Hormone (TSH) (Thyrotrophic hormone, thyrotropin)... 

TRH stimulates the anterior pituitary gland to release or secrete Thyroid-Stimulating-Hormone (TSH) (also referred to as Thyrotropin on some lab chem. Panels)... 

Thyroid hormone production is controlled by the hypothalamic-pituitary system (see Chapter 28). Thyrotropin-releasing hormone (TRH) from the hypothalamus stimulates the release of thyroid-stimulating hormone (TSH) from the anterior pituitary.17,63 TSH then travels via the systemic circulation to the thyroid gland to stimulate the production of thyroxine and triiodothyronine. 

Thyrotropin-releasing hormone, or protirelin, is a tripeptide hormone found in the paraventricular nuclei of the hypothalamus as well as in other parts of the brain. TRH is secreted into the portal venous system and stimulates the pituitary to produce thyroid-stimulating hormone (TSH, thyrotropin), which in turn stimulates the thyroid to produce thyroxine (T4) and triiodothyronine (T3). TRH stimulation of thyrotropin is blocked by thyroxine and potentiated by lack of thyroxine. 

Control of thyroid function via thyroid-pituitary feedback is also discussed in Chapter 37 Hypothalamic Pituitary Hormones. Briefly, hypothalamic cells secrete thyrotropin-releasing hormone (TRH) (Figure 38-3). TRH is secreted into capillaries of the pituitary portal venous system, and in the pituitary gland, TRH stimulates the synthesis and release of thyroid-stimulating hormone (TSH). TSH in turn stimulates an adenylyl cyclase-mediated mechanism in the thyroid cell to increase the synthesis and release of T4 and T3. These thyroid hormones act in a negative feedback fashion in the pituitary to block the action of TRH and in the hypothalamus to inhibit the synthesis and secretion of TRH. Other hormones or drugs may also affect the release of TRH or TSH. 

Regulation of synthesis Thyroid function is controlled by a tropic hormone, thyroid-stimulating hormone (TSH, thyrotropin), a glycoprotein synthesized by the anterior pituitary (see Figure 25.2). TSH generation is governed by the hypothalamic thyrotropin-... 

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