Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, B3H 4R2, Canada.
J Comp Neurol. 2014 Feb 1;522(2):456-78. doi: 10.1002/cne.23421.
The intracardiac nervous system represents the final common pathway for autonomic control of the vertebrate heart in maintaining cardiovascular homeostasis. In teleost fishes, details of the organization of this system are not well understood. Here we investigated innervation patterns in the heart of the goldfish, a species representative of a large group of cyprinids. We used antibodies against the neuronal markers zn-12, acetylated tubulin, and human neuronal protein C/D, as well as choline acetyltransferase, tyrosine hydroxylase, nitric oxide synthetase, and vasoactive intestinal polypeptide (VIP) to detect neural elements and their transmitter contents in wholemounts and sections of cardiac tissue. All chambers of the heart were innervated by choline acetyltransferase-positive axons, implying cholinergic regulation; and by tyrosine hydroxylase-containing axons, implying adrenergic regulation. The mean total number of intracardiac neurons was 713 ± 78 (SE), nearly half of which were cholinergic. Neuronal somata were mainly located in a ganglionated plexus around the sinoatrial valves. Somata were contacted by cholinergic, adrenergic, nitrergic, and VIP-positive terminals. Putative pacemaker cells, identified by immunoreactivity for hyperpolarization activated, cyclic nucleotide-gated channel 4, were located in the base of the sinoatrial valves, and this region was densely innervated by cholinergic and adrenergic terminals. We have shown that the goldfish heart possesses the necessary neuroanatomical substrate for fine, region-by-region autonomic control of the myocardial effectors that are involved in determining cardiac output.
心脏内神经系统代表了自主控制脊椎动物心脏的最后共同途径，以维持心血管稳态。在硬骨鱼类中，该系统的组织细节尚不清楚。在这里，我们研究了金鱼心脏的神经支配模式，金鱼是鲤鱼科的一个代表物种。我们使用针对神经元标志物 zn-12、乙酰化微管蛋白和人神经元蛋白 C/D 以及胆碱乙酰转移酶、酪氨酸羟化酶、一氧化氮合酶和血管活性肠肽 (VIP) 的抗体，来检测心脏组织的全器官和切片中的神经元素及其递质含量。心脏的所有腔室都被胆碱乙酰转移酶阳性轴突支配，暗示着胆碱能调节；也被含有酪氨酸羟化酶的轴突支配，暗示着肾上腺素能调节。心脏内神经元的平均总数为 713 ± 78（SE），其中近一半为胆碱能神经元。神经元体主要位于窦房结瓣周围的神经节丛中。胆碱能、肾上腺素能、氮能和 VIP 阳性终末接触神经元体。通过对超极化激活的、环核苷酸门控通道 4 的免疫反应鉴定出的假定起搏细胞位于窦房结瓣的基部，该区域被胆碱能和肾上腺素能终末密集支配。我们已经表明，金鱼心脏具有精细的、区域化的自主控制心肌效应器的必要神经解剖学基础，这些效应器参与了确定心输出量。
