Thyrotropin-releasing hormone

Description

The first hypothalamic hypophysiotropic neurohormone identified, TRH consists of the tripeptide pGlu-His-ProNH2. It stimulates the secretion ofthyroid-stimulating hormone (TSH), prolactin (PRL), and growth hormone (GH), and also functions as a neurotransmitter and neuromodulator.

Chemical properties

White or yellowish-white powder, hygroscopic.

The Uses of Thyrotropin-releasing hormone

prothyrotropin

The Uses of Thyrotropin-releasing hormone

Thyrotropin-Releasing Hormone is a hypothalamic hypophysiotropic neuropeptide, which has the ability to stimulate the release of thyroid-stimulating hormone in mammals. It is proven that Thyrotropin-Releasing Hormone can be used to accelerate wound healing.

Background

Protirelin is the pharmaceutically available synthetic analogue of the endogenous peptide thyrotropin-releasing hormone (TRH). It is a tri-peptide tropic hormone, released by the hypothalamus, that stimulates the release of Thyroid Stimulating Hormone (TSH) and prolactin from the anterior pituitary.
Although not currently available in any FDA-approved product, protirelin is a component of the TRH Test where it is used to test the response of the anterior pituitary gland in conditions such as secondary hypothyroidism and acromegaly.

Indications

Thyrotropin-releasing hormone, or protirelin, consists of three amino acids. TRH (Relefact TRH) is used for tests to distinguish primary from secondary hypothyroidism.

Definition

ChEBI: Protirelin is a tripeptide composed of L-pyroglutamyl, L-histidyl and L-prolinamide residues joined in sequence. It has a role as a human metabolite. It is a peptide hormone and a tripeptide.

General Description

Thyrotropin releasing hormone (TRH) is a tripeptide hypothalamic regulatory hormone, encoded by the gene mapped to human chromosome 3q13.3-q21. TRH is expressed in a variety of organs including central nervous system (CNS) and gastrointestinal tract.

Biochem/physiol Actions

Thyrotropin releasing hormone (TRH) stimulates production and secretion of thyrotropin (TSH) and prolactin from the anterior pituitary. It also plays a vital role as a neurotransmitter and neuromodulator.

Clinical Use

TRH (200–500μg) administered intravenously to normal subjects causes a rise in TSH levels within 15–30min, resulting in an increase in T3 levels within 90–150min. In primary hypothyroidism, TSH hyperresponse to TRH occurs, with a typical elevation in the basal TSH levels. In secondary (pituitary) hypothyroidism, an impaired TSH response to TRH occurs, whereas in tertiary (hypothalamic) hypothyroidism normal or increased TSH response to TRH occurs. Protirelin is used to test the response of the anterior pituitary to TRH in people who may have medical conditions of thyroid function, including hyperthyroidism, Graves’ disease, and hypothyroidism. In addition, TRH has been used to assess the ability of the prolactin secretion in the pituitary.

Side Effects

The peak TSH response to intravenous TRH occurs at 20 minutes. The mild and transient side effects, which occur only after intravenous TRH, include nausea, a flushing sensation, a desire to micturate, a peculiar taste, and tightness in the chest[1].

Metabolism

Not Available