Open AccessRole of pituitary adenylate cyclase‐activating polypeptide in modulating hypothalamic‐pituitary system
Author(s) -
Oride Aki,
Kanasaki Haruhiko,
Kyo Satoru
Publication year - 2018
Publication title -
reproductive medicine and biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 22
eISSN - 1447-0578
pISSN - 1445-5781
DOI - 10.1002/rmb2.12094
Subject(s) - gonadotropic cell , medicine , endocrinology , hypothalamus , receptor , prolactin , luteinizing hormone , chemistry , gonadotropin releasing hormone , hormone , anterior pituitary , biology
Background Pituitary adenylate cyclase‐activating polypeptide ( PACAP ) is a multifunctional peptide that is isolated and identified from the ovine hypothalamus, whose effects and mechanisms have been elucidated in numerous studies. The PACAP and its receptor are widely expressed, not only in the hypothalamus but also in peripheral organs. Methods The studies on the role of PACAP in the hypothalamic‐pituitary system, including those by the authors, were summarized. Results In the pituitary gonadotrophs, PACAP increases the gonadotrophin α‐, luteinizing hormoneβ‐, and follicle‐stimulating hormone β‐subunit expression and the expression of gonadotropin‐releasing hormone (Gn RH ) receptor and its own receptor, PAC 1R. Moreover, a low‐frequency Gn RH pulse increases the expression of PACAP and PAC 1R more than a high‐frequency Gn RH pulse in the gonadotrophs. The PACAP stimulates prolactin synthesis and secretion and increases PAC 1R in the lactotrophs. In the hypothalamus, PACAP increases the expression of the Gn RH receptors, although it is unable to increase the expression of Gn RH in the Gn RH ‐producing neurons. Conclusion The PACAP not only acts directly in each hormone‐producing cell, it possibly might regulate hormone synthesis via the expression of its own receptors or those of other hormones.