Processing of the luteinizing hormone-releasing hormone precursor in the preoptic area and hypothalamus of the rat.

Published

Journal Article

The LHRH precursor is known to contain the decapeptide and a 56 amino acid peptide termed gonadotropin-releasing hormone-associated peptide (GAP). The purpose of our study was to characterize the proLHRH and its processed products from the cell body and fiber region and from the nerve terminal region of LHRH neurons. The median eminence (ME) and a tissue block containing the preoptic area and hypothalamus (POH) were dissected separately. Tissues were homogenized and peptides were separated according to mol wt. Three different LHRH antisera bound to one immunoreactive (IR) substance which eluted at approximately 1200 mol wt. Subsequently, this material coeluted with synthetic LHRH on a reversed-phase column as a single peak. There was approximately 1.6-fold more LHRH-like IR in the ME than in the POH. The four different GAP antisera recognized multiple mol wt forms of GAP-like IR at approximately 16,000 to 14,000, 8,200, 6,500, 3,500, and 2,800 mol wt. There were more of the high mol wt materials and less of the 6500 and lower mol wt materials in the POH than in the ME. The most abundant species in both regions was the 6500 mol wt form. This IR substance coeluted with synthetic rat GAP1-56 on a reversed-phase column as a single peak. These experiments demonstrate 1) that multiple IR forms of the LHRH prohormone exist in the POH of the rat and 2) that nerve terminals of the LHRH neurons contain LHRH, GAP1-56, and some lower mol wt GAP-like substances. These results provide the first information concerning the processing scheme for the LHRH prohormone in the rat brain.

Full Text

Duke Authors

Cited Authors

  • Wetsel, WC; Culler, MD; Johnston, CA; Negro-Vilar, A

Published Date

  • January 1988

Published In

Volume / Issue

  • 2 / 1

Start / End Page

  • 22 - 31

PubMed ID

  • 3041260

Pubmed Central ID

  • 3041260

International Standard Serial Number (ISSN)

  • 0888-8809

Digital Object Identifier (DOI)

  • 10.1210/mend-2-1-22

Language

  • eng

Conference Location

  • United States