Central and peripheral administration of kisspeptin activates gonadotropin but not somatotropin secretion in prepubertal gilts.
It is well established that kisspeptin signaling is necessary for the onset of puberty in laboratory animals. However, the role that kisspeptin may have in regulating puberty in large domestic animals is unknown. We tested the hypothesis that either central or peripheral infusion of kisspeptin would stimulate gonadotropin and GH secretion in prepubertal gilts. In experiment 1, prepubertal gilts were fitted with i.c.v. cannula and indwelling jugular catheters. Animals were randomly assigned to receive 0, 10, or 100 microg kisspeptin in saline. In experiment 2, prepubertal gilts, fitted with indwelling jugular catheters, randomly received 0, 1, 2.5, or 5 mg kisspeptin in saline intravenously. Serial blood samples were collected every 15 min for 3 h before and 5 h after infusions, and serum concentrations of LH, FSH, and GH were determined. Mean concentrations of LH and FSH remained at basal levels for control animals but were increased (P<0.001) for animals receiving i.c.v. infusion of kisspeptin. Area under the LH and FSH curves following i.c.v. infusion of kisspeptin increased (P<0.001) in a dose-dependent manner. Concentrations of GH were unaffected by i.c.v. treatment. Peripheral administration of kisspeptin increased (P<0.05) serum concentrations of LH but not FSH or GH. Thus, kisspeptin can activate gonadotropic but not somatotropic hormone secretion in prepubertal gilts. The present data support the concept that kisspeptin plays a role in the mechanism involved in initiating puberty in swine.
Lents
Clay A
CA
Department of Animal and Dairy Science, College of Agricultural and Environmental Sciences, 316 Edgar L Rhodes Center for Animal and Dairy Science, The University of Georgia, Athens, Georgia 30602-2771, USA. 68933, USA. clents@uga.edu
Heidorn
Neely L
NL
Barb
C Richard
CR
Ford
J Joe
JJ
D000818:Animals; D002404:Catheterization; D002550:Cerebral Veins; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood / Q000378:metabolism; D007987:Gonadotropin-Releasing Hormone / Q000494:pharmacology; D006065:Gonadotropins, Pituitary / Q000097:blood / Q000378:metabolism*; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism*; D007262:Infusions, Intravenous; D007601:Jugular Veins; D059648:Kisspeptins; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism*; D011863:Radioimmunoassay; D011897:Random Allocation; D012741:Sexual Maturation / Q000187:drug effects*; D013552:Swine / Q000502:physiology*; D025521:Tumor Suppressor Proteins / Q000008:administration & dosage* / Q000494:pharmacology
D006065:Gonadotropins, Pituitary; C491407:Kiss1 protein, mouse; D059648:Kisspeptins; D025521:Tumor Suppressor Proteins; D007987:Gonadotropin-Releasing Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D013006:Growth Hormone