The gonadotropin‐releasing hormone family of neuropeptides in the brain of human, bovine and rat: identification of a third isoform

FEBS Letters

Koch, Yitzhak¹  Okon, Eli²  Yahalom, Dror¹  Rahimipour, Shai¹  Fridkin, Mati³  Ben-Aroya, Nurit¹  Kaganovsky, Ella²  Chen, Alon¹ 

[1] Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel;Department of Pathology, Rabin Medical Center, Petah-Tikva 49100, Israel;Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel

关键词: Gonadotropin-releasing hormone/luteinizing hormone-releasing hormone isoform;    Gonadotropin-releasing hormone;    third isoform in mammalian brain;    Salmon gonadotropin-releasing hormone-like peptide in mammals;    BSA;    bovine serum albumin;    GnRH;    gonadotropin-releasing hormone;    HPLC;    high-performance liquid chromatography;    LH;    luteinizing hormone;    RIA;    radioimmunoassay;    RP;    reversed phase;    TFA;    trifluoroacetic acid;   

DOI  :  10.1016/S0014-5793(99)01638-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

The mammalian gonadotropin-releasing hormone (GnRH-I), which regulates reproduction, was the first isoform of GnRH that was identified in mammals. Recently, we and others have demonstrated the existence of a second isoform of GnRH in the brain of mammals. The presence of a third isoform of GnRH, GnRH-III, in the brain of mammals is reported herein. GnRH-III, extracted from the brain of bovine and human, was purified by high performance liquid chromatography, using two distinct elution programs. In both, GnRH-III was eluted at the same positions as synthetic salmon GnRH, as demonstrated by radioimmunoassay. The luteinizing hormone-releasing activity of purified GnRH-III, using dispersed rat pituitary cells, was found to be similar to that of synthetic salmon GnRH. The total amount of GnRH-III, determined by radioimmunoassay, in the hypothalamus and midbrain of humans and calves is similar to that of GnRH-I. Immunohistochemical studies demonstrated GnRH-III-containing neurons in the hypothalamus and midbrain of human and GnRH-III fibers in the median eminence of rats. The distribution of GnRH-III in the brain suggests that in addition to a putative function as a neurohormone at the hypothalamic–pituitary axis, GnRH-III may have other functions. Our present results suggest that multiple isoforms of GnRH are present in the brain of mammals, and further studies are required in order to elucidate their biological functions.

【 授权许可】

Unknown