A role for GABA agonist in controlling the reproduction of female rats via hypothalamic ghrelin, kisspeptin, and RFRP-3 gene expression

Iranian Journal of Veterinary Science and Technology

مقاله 5، دوره 13، شماره 1 - شماره پیاپی 24، پاییز و زمستان 2021، صفحه 42-47  

نوع مقاله: Research Article

شناسه دیجیتال (DOI): 10.22067/ijvst.2021.64272.0

نویسندگان

Elaheh Rahimi Rick¹؛ Fariba Mahmoudi ¹؛ Homayoun khazali²؛ Asadollah Asadi¹؛ Mahnaz Ghowsi³

¹Faculty of Sciences, University of Mohaghegh Ardabili, Ardabil, Iran.

²Department of Animal Science and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran.

³Department of Biology, Faculty of sciences, Razi University, Kermanshah. Iran.

چکیده

   Kisspeptin stimulates gonadotropin releasing hormone (GnRH). The GnRH neurons receive inhibitory inputs from ghrelin, RFamide related peptide-3 (RFRP-3), and gamma-aminobutyric acid (GABA) neurons. Polycystic ovary syndrome (PCOS) is associated with increased levels of GnRH/LH and kisspeptin, and decreased release of GABA, ghrelin,  and RFRP-3. In the present study, the effects of GABAB receptor agonist, baclofen, were investigated on GnRH, KiSS1, RFRP-3, and ghrelin gene expression in the hypothalamus of PCOS model rats. For induction of PCOS, female Wistar rats weighing 180-200g received intra-muscular injection of estradiol valerate. Fifteen PCOS rats in three groups received intraperitoneal injections of saline, 5, or 10 mg/kg baclofen for two weeks. The hypothalamic samples were dissected. Gene expression levels of GnRH, KiSS1, RFRP-3, and ghrelin were determined by real time qPCR method. Results revealed that baclofen significantly decreased the mean relative KiSS1 gene expression compared to PCOS group. Also, the mean relative RFRP-3 gene expression significantly increased in the baclofen-receiving rats in comparison to PCOS group. Furthermore, baclofen did not change GnRH or ghrelin mRNA levels in comparison to PCOS group. According to these results it can be concluded that in PCOS condition the GABAergic signaling pathway may suppress GnRH neural activity via down or up regulation of the intra-hypothalamic neuropeptides upstream of GnRH neurons.

کلیدواژه‌ها

Baclofen؛ GnRH؛ kisspeptin؛ ghrelin؛ RFRP-3

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