title: Central injection of ketone body suppresses luteinizing hormone release via the catecholaminergic pathway in female rats.
abstract: Ketosis is found in various pathophysiological conditions, including diabetes and starvation, that are accompanied by suppression of gonadal activity. The aim of the present study was to determine the role of ketone body in the brain in regulating pulsatile luteinizing hormone (LH) secretion in female rats. Injection of 3-hydroxybutyrate (3HB), a ketone body, into the fourth cerebroventricle (4V) induced suppression of pulsatile LH secretion in a dose-dependent manner in ovariectomized (OVX) rats with an estradiol (E2) implant producing diestrus plasma E2 levels. Plasma glucose and corticosterone levels increased immediately after the 4V 3HB injection, suggesting that the treatment caused a hunger response. The 3HB-induced suppression of LH pulses might be mediated by noradrenergic inputs to the hypothalamic paraventricular nucleus (PVN) because a local injection of α-methyl- p-tyrosine, a catecholamine synthesis inhibitor, into the PVN blocked 3HB-induced suppression of LH pulses and PVN noradrenaline release was increased by 4V 3HB injection in E2-primed OVX rats. These results suggest that ketone body sensed by a central energy sensor in the hindbrain may suppress gonadotropin release via noradrenergic inputs to the PVN under ketosis.
authors.affiliation: Laboratory for Reproductive Science, Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan..
authors.forename: Kinuyo
authors.initials: K
authors.lastname: Iwata
authors.forename: Mika
authors.initials: M
authors.lastname: Kinoshita
authors.forename: Naoki
authors.initials: N
authors.lastname: Susaki
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Uenoyama
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tsukamura
authors.forename: Kei-ichiro
authors.initials: K
authors.lastname: Maeda
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000008:administration & dosage; D000818:Animals; D001786:Blood Glucose / Q000187:drug effects; D002395:Catecholamines / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D003345:Corticosterone / Q000097:blood; D005260:Female; D020546:Fourth Ventricle / Q000187:drug effects; D007657:Ketone Bodies / Q000008:administration & dosage*; D007986:Luteinizing Hormone / Q000378:metabolism*; D010286:Paraventricular Hypothalamic Nucleus / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D019805:alpha-Methyltyrosine / Q000008:administration & dosage
chemical_list: D001786:Blood Glucose; D002395:Catecholamines; D007657:Ketone Bodies; D019805:alpha-Methyltyrosine; D007986:Luteinizing Hormone; D020155:3-Hydroxybutyric Acid; D003345:Corticosterone