Lychkova Alla Edward, De Pasquale Valeria, Avallone Luigi, Puzikov Alexander Michael, Pavone Luigi Michele
Central Research Institute of Gastroenterology, Shosse Enthusiasts 86, 111123 Moscow, Russian Federation.
Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
Comp Biochem Physiol C Toxicol Pharmacol. 2014 Sep;165:53-9. doi: 10.1016/j.cbpc.2014.05.006. Epub 2014 Jun 2.
Serotonin (5-HT) can stimulate the cholinergic system of the uterus by indirect actions on the modulation of reflexes and a direct action on smooth muscles. We investigated the role of 5-HT in the regulation of the cholinergic activity in the uterine parts of non-pregnant rabbits. The right vagus or pelvic nerve and the left sympathetic trunk were stimulated by an electrical field, and the uterine contractile activity was evaluated by measuring the amplitude and frequency of slow wave electromyogram (EMG), with the surface of microelectrodes applied to the uterus bottom, body, and cervix, respectively. Double stimulation of the vagus or pelvic nerve and the sympathetic trunk increased the frequency and the amplitude of the slow wave EMG in all the uterine parts. Furthermore, the administration of exogenous 5-HT increased the vagus or pelvic induced EMG activity in all parts of the uterus. Overall our results demonstrate that 5-HT enhances the vagus contractile activity with a magnitude of the effect decreasing from the bottom to the cervix, whereas 5-HT enhances the pelvic nerve contractile functions with a magnitude of the response increasing from the bottom to the cervix. The administration of droperidol, a 5-HT3 and 4 receptor inhibitor, and spiperone, a 5-HT2 receptor antagonist, inhibited the effect of the serotoninergic fibers of the sympathetic trunk to increase the vagus and pelvic nerve EMG activity. These data suggest that 5-HT stimulation of the parasympathetic nerves results in the induction of uterine contraction via the activation of 5-HT2, 3, and 4 receptor subfamilies.
血清素（5-羟色胺，5-HT）可通过对反射调节的间接作用以及对平滑肌的直接作用来刺激子宫的胆碱能系统。我们研究了5-HT在非妊娠兔子宫部位胆碱能活性调节中的作用。通过电场刺激右侧迷走神经或盆神经以及左侧交感干，分别将微电极表面置于子宫底部、体部和宫颈，通过测量慢波肌电图（EMG）的幅度和频率来评估子宫收缩活动。对迷走神经或盆神经与交感干进行双重刺激可增加所有子宫部位慢波EMG的频率和幅度。此外，给予外源性5-HT可增加子宫各部位迷走神经或盆神经诱导的EMG活动。总体而言，我们的结果表明，5-HT增强迷走神经收缩活动，其作用强度从子宫底部到宫颈逐渐减弱，而5-HT增强盆神经收缩功能，其反应强度从子宫底部到宫颈逐渐增强。给予5-HT3和4受体抑制剂氟哌利多以及5-HT2受体拮抗剂螺哌隆，可抑制交感干中5-羟色胺能纤维增加迷走神经和盆神经EMG活动的作用。这些数据表明，5-HT对副交感神经的刺激通过激活5-HT2、3和4受体亚家族导致子宫收缩。
