These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Hypophysiotropic thyrotropin-releasing hormone-synthesizing neurons in the human hypothalamus are innervated by neuropeptide Y, agouti-related protein, and alpha-melanocyte-stimulating hormone.
    Author: Mihály E, Fekete C, Tatro JB, Liposits Z, Stopa EG, Lechan RM.
    Journal: J Clin Endocrinol Metab; 2000 Jul; 85(7):2596-603. PubMed ID: 10902813.
    Abstract:
    We recently demonstrated that three arcuate nucleus-derived peptides, neuropeptide Y (NPY), agouti-related protein (AGRP), and alphaMSH, are contained in axon terminals that heavily innervate hypophysiotropic TRH neurons in the rat brain and may contribute to the altered set-point of the hypothalamo-pituitary-thyroid axis during fasting. To determine whether a similar regulatory system exists in human brain, we performed a series of immunohistochemical studies using antisera against NPY, AGRP, alphaMSH, and TRH in adult hypothalami obtained within 15 h of death. Numerous small to medium-sized, fusiform and multipolar NPY-, AGRP-, and alphaMSH-immunoreactive (-IR) cells were widely distributed throughout the rostro-caudal extent of the infundibular (arcuate) nucleus. A similar distribution pattern was found for NPY- and AGRP-IR neurons in the arcuate nucleus, whereas alphaMSH-IR cells appeared to form a separate cell population. By double labeling fluorescent immunohistochemistry, 82% of NPY neurons cocontained AGRP, and 87% of AGRP neurons coexpressed NPY. No colocalization was found between alphaMSH- and AGRP-IR neurons. NPY-, AGRP-, and alphaMSH-containing axons densely innervated the hypothalamic paraventricular nucleus and were found in close juxtaposition to TRH-synthesizing cell bodies and dendrites. These studies demonstrate that in man, the NPY-, AGRP-, and alphaMSH-IR neuronal systems in the infundibular and paraventricular nuclei are highly reminiscent of that observed in the rat and may similarly be involved in regulating the hypothalamo-pituitary-thyroid axis in the human brain.
    [Abstract] [Full Text] [Related] [New Search]