Thyrotropin-releasing hormone (TRH) is a tripeptide hormone produced by the hypothalamus that plays a critical role in regulating the thyroid function by stimulating the secretion of thyroid-stimulating hormone (TSH) from the anterior pituitary gland. In addition to its endocrine function, TRH is also involved in modulating the autonomic nervous system, influencing mood, and other neuroendocrine activities.