Thyroid-stimulating hormone (also known as TSH or thyrotropin) is a peptide hormone synthesized and secreted by thyrotrope cells in the anterior pituitary gland, which regulates the endocrine function of the thyroid gland. Description: Human pituitary glands. Alternative Names: Thyrotropin alpha subunit protein, Thyroid Stimulating Hormone alpha protein, Thyroid Stimulation Hormone protein