Effect of Peripheral Administration of Kisspeptin-10 on Dynamic LH Secretion in Prepubertal Ewes
نویسندگان
چکیده
The aim of the present study was to clarify the effect of kisspeptin-10 on LH secretion in prepubertal ewes. In experiment 1, prepubertal ewes fitted with indwelling jugular catheters were randomly assigned to receive 0, 0.5, 1 or 2 mg of kisspeptin-10 dissolved in saline, and serial blood samples were collected at 15-min intervals for 180 min to analyze the response curves of LH after injection. In experiment 2, prepubertal ewes fitted with indwelling jugular catheters were injected with 0 or 1 mg of kisspeptin-10 dissolved in saline and the injection was repeated 3 times at 1 h interval and serial blood samples were collected at 15-min intervals for 210 min to analyze the response curves of LH after injection. The results showed that single intravenous administration of 0.5, 1 and 2 mg of kisspeptin-10 all could significantly increased LH secretion in prepubertal ewes, and the effect of 1 and 2 mg of kisspeptin-10 on LH secretion was higher than that of 0.5 mg group. The results also showed that repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion and repeated administration did not influence the effect of kisspeptin-10 on LH secretion in prepubertal ewe. In conclusion, the present study indicated that single or repeated intravenous administration of kisspeptin-10 could effectively increase LH secretion in prepubertal ewes.
منابع مشابه
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...
متن کاملO-14: Effect of Kisspeptin on Testicular Tissue and Accessory Sex Glands, Seminal Vesicle and Prostate, in Prepubertal Rats
Background: Hypothalamus-derived kisspeptins are critical regulators of reproduction in nearly all mammalian species including the humans. These small peptides mediate their actions through the GnRH loop system. How kisspeptins regulate gonadal maturation in sexually immature male mammals remains elusive. To address this, kisspeptin was administered as subchronic (12 days) twice daily i. p. dos...
متن کاملHypothalamic KiSS1/GPR54 Gene Expressions and Luteinizing Hormone Plasma Secretion in Morphine Treated Male Rats
Objective The inhibitory effects of Morphine and the stimulatory influence of kisspeptin signaling have been demonstrated on GnRH/LH release. Hypothalamic kisspeptin is involved in relaying the environmental and metabolic information to reproductive axis. In the present study the role of kisspeptin/GPR54 signaling system was investigated on relaying the inhibitory effects of morphine on LH horm...
متن کاملGPR54-Dependent Stimulation of Luteinizing Hormone Secretion by Neurokinin B in Prepubertal Rats
Kisspeptin, neurokinin B (NKB) and dynorphin A (Dyn) are coexpressed within KNDy neurons that project from the hypothalamic arcuate nucleus (ARC) to GnRH neurons and numerous other hypothalamic targets. Each of the KNDy neuropeptides has been implicated in regulating pulsatile GnRH/LH secretion. In isolation, kisspeptin is generally known to stimulate, and Dyn to inhibit LH secretion. However, ...
متن کاملEvidence that dopamine acts via kisspeptin to hold GnRH pulse frequency in check in anestrous ewes.
Recent work has implicated stimulatory kisspeptin neurons in the arcuate nucleus (ARC) as important for seasonal changes in reproductive function in sheep, but earlier studies support a role for inhibitory A15 dopaminergic (DA) neurons in the suppression of GnRH (and LH) pulse frequency in the nonbreeding (anestrous) season. Because A15 neurons project to the ARC, we performed three experiments...
متن کامل