mRNA Expression of Kisspeptin, Neurokinin B and Dynorphin in the Celiac Ganglion during Reproductive Ageing

Presentation Number: LBF-079
Date of Presentation: March 6th, 2015

Alfonso Humberto Paredes*1, Hernan E Lara2 and Daniela Fernandois3
1Universidad de Chile, Santiago, Chile, Chile, 2University of Chile, Santiago, Chile, 3University of Chile, Santiago

Abstract

Kisspeptin, Neurokin B and Dynorphin (KNDy) are peptides involved in GnRH neurons regulation and in the ovulatory process through its action in the central nervous system.  At the peripheral nervous system, Kisspeptin colocalize with tyrosine hydroxylase in sympathetic neurons of the celiac ganglion (CG) projecting its axons into the rat ovary to locally regulates ovary function opening the interesting possibility that Kiss and noradrenaline (NA) could interact in a cooperative fashion to regulates ovary function.

Considering that ageing of the ovary is characterized by increased NA concentration and in the activity of sympathetic nerves (originated at CG), it is possible that these peptides which are closely related to central regulation of reproduction, could also increases during development and participate in the neurogenic-dependent increase in ovarian follicular cysts-accompanying the ageing of the ovary.

The main purpose of this work was to determine the changes in Kisspeptin Neurokinin B and KNDy mRNA levels during reproductive ageing to relate these changes to ovary function.

Ovary and CG were collected from Sprague-Dawley rat of different age, fertile (6 month old), subfertile (8 to 10 month old) and infertile (12 month old). The mRNA content for KNDy were determined by RT-qPCR, using a IQ5 Biorad Real time PCR in CG and ovary, The protein level was determinated in the rata ovary (by western blot analysis). Rats from 6 to 12 months old showed increased of mRNA and peptide for Kisspeptin at subfertile period, followed by a decrease at 12-month old. In the CG, Kisspeptin mRNA decreased during subfertile period. However, Dy and NKB receptor mRNA levels did not change during reproductive aging but Neurokinin B increased at 8 month old followed by a decrease at 10 month old

In conclusion, we demonstrated for the first time that celiac ganglion cells express KNDy system, Neurokinin and dynorphin being potential local regulators of ovary function and thus in follicular ageing.

Supported by Grant Fondecyt 1120147

 

Nothing to Disclose: AHP, HEL, DF