Beaulieu P, Lambert C
Department of Pharmacology, Faculty of Medicine, Université de Montréal, Québec, Canada.
Cardiovasc Res. 1998 Mar;37(3):578-85. doi: 10.1016/s0008-6363(97)00305-2.
Autonomic influences on the heart rate have been the subject of intense research for many decades and are classically devoted to the sympathetic and parasympathetic systems. However, developments over the past few years in our knowledge of the organization of the autonomic nervous system have led to the conclusion that in addition to the classical transmitters, peptidic transmitters are clearly present and have direct or indirect actions on cardiac conduction. Neuropeptides have been found to collocate with each other or with classical transmitters, thereby increasing the variety of chemical signals that a neuron can utilize to communicate with other cells. Neuropeptides can act as neurotransmitters, neuromodulators or neurohormones. Some are produced in endocrine glands and circulate as hormones, while others are contained in cardiac myocytes, neurons, or endothelial cells in proximity to the sinoatrial node and can therefore act in a paracrine or autocrine way on the pacemaker cells to modulate heart frequency. There is evidence supporting such a role, especially for locally situated neuropeptide Y, vasoactive intestinal peptide, calcitonin gene-related peptide, substance P, angiotensin II, natriuretic peptides, endothelins and possibly many others. The role of the peptidic neurotransmitters in the conduction system should not be exaggerated. Nevertheless, neuropeptides certainly represent a new category of neurotransmitters forming a third component of the autonomic nervous system and may have complex actions with potential therapeutic implications in man.
几十年来，自主神经系统对心率的影响一直是深入研究的课题，传统上主要关注交感神经系统和副交感神经系统。然而，过去几年我们对自主神经系统组织结构的认识发展，得出了这样的结论：除了经典递质外，肽类递质也明显存在，并对心脏传导有直接或间接作用。已发现神经肽相互并存或与经典递质并存，从而增加了神经元可用于与其他细胞通讯的化学信号种类。神经肽可作为神经递质、神经调质或神经激素发挥作用。有些在内分泌腺中产生并作为激素循环，而另一些则存在于窦房结附近的心肌细胞、神经元或内皮细胞中，因此可通过旁分泌或自分泌方式作用于起搏细胞，调节心率。有证据支持这种作用，特别是对于局部存在的神经肽Y、血管活性肠肽、降钙素基因相关肽、P物质、血管紧张素II、利钠肽、内皮素以及可能的许多其他物质。肽类神经递质在传导系统中的作用不应被夸大。然而，神经肽无疑代表了一类新的神经递质，构成自主神经系统的第三个组成部分，并且可能在人类中具有具有潜在治疗意义的复杂作用。
