Thyrotropin-Releasing Hormone TRH

Thyrotropin-releasing factor (TRF) = thyrotropin-releasing hormone (TRH) = thyroliberin. 

The BZ stmcture also has provided a molecular scaffold for a number of peptide receptor ligands (26). Antagonists for the cholecystokinin (CCK-A) receptor, eg, devazepide (65), the thyrotropin-releasing hormone (TRH) receptor, eg, midazolam (66), and the /i -opiate receptor, eg, tifluadom (67), as well as a series of ras famyl transferase inhibitors, eg, BZA-2B (68) (30) have been identified (Table 4). 

Prolactin is an essential hormone for normal production of breast milk following childbirth. It also plays a pivotal role in a variety of reproductive functions. Prolactin is regulated primarily by the hypothalamus-pituitary axis and secreted solely by the lactotroph cells of the anterior pituitary gland. Under normal conditions, secretion of prolactin is predominantly under inhibitory control by dopamine and acts on the D2 receptors located on the lactotroph cells. Increase of hypothalamic thyrotropin-releasing hormone (TRH) in primary hypothyroidism can stimulate the release of prolactin. 

Werner, U., T. Kissel, and W. Stuber. Effects of peptide structure on transport properties of seven thyrotropin releasing hormone (TRH) analogues in a human intestinal cell line (Caco-2), Pharm. Res. 1997, 14, 246-250... 

Moss, J., Bundgaard, FI., Prodrugs of peptides 8. In vitro study of intestinal metabolism and penetration of thyrotropin-releasing hormone (TRH) and its prodrugs, Int. J. Pharm. 1990, 66, 39-45. 

Thwaites DT, Hirst BH, Simmons NL (1993) Passive transepithelial absorption of thyrotropin-releasing hormone (TRH) via a paracellular route in cultured intestinal and renal epithelial cell lines. Pharm Res 10 674-681. 

K. Ohki, N. Sakura, T. Hashimoto, Hydrolytic Cleavage of Pyroglutamyl-Peptide Bond. IV. Highly Selective Cleavage of Thyrotropin-Releasing Hormone (TRH) in Aqueous Methanesulfonic Acid , Chem. Pharm. Bull. 1997, 45, 194-197. 

H. Bundgaard, J. Mpss, Prodrugs of Peptides. 6. Bioreversible Derivatives of Thyrotropin-Releasing Hormone (TRH) with Increased Lipophilicity and Resistance to Cleavage by the TRH-Specific Serum Enzyme , Pharm. Res. 1990, 7, 885-892. 

Thyroliberin (thyrotropin-releasing hormone, TRH) is one of the neurohormones of the hypothalamus (see p. 330). It stimulates pituitary gland cells to secrete thyrotropin (TSH). TRH consists of three amino acids, which are modified in characteristic ways (see p. 353). 

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. 

Nemeroff CB, Bissette G, Martin JB, et al Effect of chronic treatment with thyrotropin-releasing hormone (TRH) or an analog of TRH (hnear-beta-alanine TRH) on the hypothalamic-pituitary-thyroid axis. Neuroendocrinology 30 193-199, 1980... 

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