10:45 〜 11:00
[IIYS-08E] The role of calcitonin receptor signaling on the GnRH pulse generator activity in goats
Pulsatile gonadotropin-releasing hormone (GnRH) secretion is indispensable for the regulation of reproductive functions. Kisspeptin neurons localized in the hypothalamic arcuate nucleus (ARC) are considered to be the neural unit comprising the GnRH pulse generator, which governs pulsatile GnRH release. Recently, we reported that the ARC kisspeptin neurons in rats express calcitonin receptor (CTR). In the present study, we first confirmed the CTR mRNA expression in goat brain by RT-PCR and in situ hybridization. CTR mRNA was widely distributed in brain areas beside the 3rd cerebral ventricle in ovariectomized goats. Next, we examined effects of intraventricular injection of amylin, an endogenous ligand of CTR, on the GnRH pulse generator activity. The activity was immediately stimulated after amylin injection and then suppressed. These results suggest that central CTR signaling has both stimulatory and inhibitory role in the regulation of the GnRH pulse generator activity in goats.