Department of Biomedical Sciences, School of Medicine and Health Sciences, University of North Dakota, Grand Forks, ND 58203, USA.
Cereb Cortex. 2021 Mar 31;31(5):2402-2415. doi: 10.1093/cercor/bhaa363.
Oxytocin (OXT) is a nonapeptide that serves as a neuromodulator in the brain and a hormone participating in parturition and lactation in the periphery. The subiculum is the major output region of the hippocampus and an integral component in the networks that process sensory and motor cues to form a cognitive map encoding spatial, contextual, and emotional information. Whilst the subiculum expresses the highest OXT-binding sites and is the first brain region to be activated by peripheral application of OXT, the precise actions of OXT in the subiculum have not been determined. Our results demonstrate that application of the selective OXT receptor (OXTR) agonist, [Thr4,Gly7]-oxytocin (TGOT), excited subicular neurons via activation of TRPV1 channels, and depression of K+ channels. The OXTR-mediated excitation of subicular neurons required the functions of phospholipase Cβ, protein kinase C, and degradation of phosphatidylinositol 4,5-bisphosphate (PIP2). OXTR-elicited excitation of subicular neurons enhanced long-term potentiation via activation of TRPV1 channels. Our results provide a cellular and molecular mechanism to explain the physiological functions of OXT in the brain.
催产素（OXT）是一种九肽，作为大脑中的神经调节剂，以及参与分娩和哺乳期外周的激素。下托是海马体的主要输出区域，也是处理感觉和运动线索以形成编码空间、上下文和情感信息的认知图的网络的组成部分。虽然下托表达最高的 OXT 结合位点，并且是第一个通过外周应用 OXT 激活的大脑区域，但 OXT 在该区域的确切作用尚未确定。我们的研究结果表明，选择性 OXT 受体（OXTR）激动剂 [Thr4，Gly7]-催产素（TGOT）的应用通过激活 TRPV1 通道和抑制 K+通道兴奋下托神经元。OXTR 介导的下托神经元兴奋需要磷脂酶 Cβ、蛋白激酶 C 和磷酸肌醇 4,5-二磷酸（PIP2）的降解的功能。OXTR 诱导的下托神经元兴奋通过激活 TRPV1 通道增强长时程增强。我们的研究结果提供了一种细胞和分子机制来解释 OXT 在大脑中的生理功能。
