Thyrotropin-Releasing Hormone

Abstract

The modern era of neuroendocrinology was ushered in just over a decade ago with the isolation and characterization, from ovine¹ and porcine² hypothalamic tissue, of a tripeptide (pyroglutamyl-histidyl-proline amide), which was designated thyrotropin-releasing hormone (TRH) by virtue of its capacity to stimulate the release of thyroid-stimulating hormone (TSH) from the mammalian anterior pituitary. Later, it was found that TRH was equally effective in stimulating prolactin secretion from the normal pituitary gland.³ Although the importance of this hypothalamic releasing factor in the regulation of the pituitary-thyroid axis in human beings and other mammals has been established,⁴ most studies do not accord . . .