Salehi Mohammad Saied, Khazali Homayoun, Mahmoudi Fariba, Janahmadi Mahyar
Department of Physiology, Faculty of Biological Sciences and Technology, Shahid Beheshti University, Tehran, Iran.
Faculty of Basic Sciences, University of Mohaghegh Ardabili, Ardabil, Iran.
J Mol Neurosci. 2017 Aug;62(3-4):356-362. doi: 10.1007/s12031-017-0943-8. Epub 2017 Jun 29.
The last decade has witnessed a surge in studies on the clinical applications of intranasal oxytocin as a method of enhancing social interaction. However, the molecular and cellular mechanisms underlying its function are not completely understood. Since oxytocin is involved in the regulation of hypothalamic-pituitary-gonadal axis by affecting the gonadotropin-releasing hormone (GNRH) system, the present study addressed whether intranasal application of oxytocin has a role in affecting GNRH expression in the male rat hypothalamus. In addition, we assessed expression of two excitatory (kisspeptin and neurokinin B) and two inhibitory (dynorphin and RFamide-related peptide-3) neuropeptides upstream of GNRH neurons as a possible route to relay oxytocin information. Here, adult male rats received 20, 40, or 80 μg oxytocin intranasally once a day for 10 consecutive days, and then, the posterior (PH) and anterior hypothalamus (AH) dissected for evaluation of target genes. Using qRT-PCR, we found that oxytocin treatment increased Gnrh mRNA levels in both the PH and AH. In addition, oxytocin at its highest dose increased kisspeptin expression in the AH by around 400%, whereas treatments, dose dependently decreased kisspeptin mRNA in the PH. The expression of neurokinin B was increased from the basal levels following the intervention. Furthermore, although intranasal-applied oxytocin decreased hypothalamic RFamide-related peptide-3 mRNA level, the dynorphin mRNA was not affected. These observations are consistent with the hypothesis that applications of intranasal oxytocin can affect the GNRH system.
在过去十年中，鼻腔内使用催产素作为增强社交互动方法的临床应用研究激增。然而，其功能背后的分子和细胞机制尚未完全明确。由于催产素通过影响促性腺激素释放激素（GNRH）系统参与下丘脑-垂体-性腺轴的调节，本研究探讨了鼻腔内应用催产素是否对雄性大鼠下丘脑GNRH表达有影响。此外，我们评估了GNRH神经元上游两种兴奋性神经肽（亲吻素和神经激肽B）和两种抑制性神经肽（强啡肽和RF酰胺相关肽-3）的表达，作为传递催产素信息的可能途径。在此，成年雄性大鼠连续10天每天鼻腔内给予20、40或80μg催产素，然后解剖下丘脑后部（PH）和前部（AH）以评估靶基因。使用qRT-PCR，我们发现催产素处理增加了PH和AH中Gnrh mRNA水平。此外，最高剂量的催产素使AH中的亲吻素表达增加约400%，而处理则使PH中的亲吻素mRNA剂量依赖性降低。干预后神经激肽B的表达从基础水平增加。此外，尽管鼻腔内应用催产素降低了下丘脑RF酰胺相关肽-3 mRNA水平，但强啡肽mRNA未受影响。这些观察结果与鼻腔内应用催产素可影响GNRH系统的假设一致。
