Kapadia S E, de Lanerolle N C, LaMotte C C
Neuroscience. 1985 Jul;15(3):729-46. doi: 10.1016/0306-4522(85)90075-2.
Serotonin neurons in the dorsal raphe nucleus were identified using an antibody to a serotonin-bovine serum albumin conjugate and the peroxidase anti-peroxidase method. Nerve cell bodies showing serotonin-like immunoreactivity ranged in size from 15 to 22 micron in diameter; their dendrites were also immunoreactive. Immunostaining was present in the cytoplasmic matrix, outer membranes of mitochondria, rough endoplasmic reticulum, multivesicular bodies and dense-cored vesicles. Heavily immunoreactive axonal varicosities contained small round vesicles (18-35 nm) and larger dense-cored vesicles (50-90 nm). Both unmyelinated (0.2-0.5 micron) and myelinated (0.8-1.1 micron) serotonin-like immunoreactive axons were found, often interspersed within bundles of similar caliber unlabeled axons. Serotonin-like immunoreactive somata and dendrites were postsynaptic to numerous unlabeled terminals that contained either (a) clear round vesicles (18-25 nm) with many small dense-cored vesicles (30-50 nm), (b) clear round vesicles (18-25 nm) with large dense-cored vesicles (90-110 nm) or (c) clear round vesicles (18-25 nm) with or without flat vesicles. In addition pairs of unlabeled terminals formed crest synapses onto serotonin-like immunoreactive dendritic spines. This variety of unlabeled terminals making contact with serotonin-like immunoreactive elements suggests that several neuronal systems with possibly different transmitters may regulate serotonin raphe neurons. We occasionally observed serotonin-like immunoreactive dendrites and terminals in apposition to other serotonin-like immunoreactive dendrites with membrane specializations at the site of contact. This might represent a possible site for the self inhibition of serotoninergic neurons reported in physiological studies of the serotonin system in the dorsal raphe nucleus.
使用抗血清素 - 牛血清白蛋白偶联物的抗体和过氧化物酶抗过氧化物酶方法鉴定中缝背核中的血清素神经元。显示血清素样免疫反应性的神经细胞体直径范围为15至22微米；它们的树突也具有免疫反应性。免疫染色存在于细胞质基质、线粒体的外膜、粗面内质网、多囊体和致密核心小泡中。高度免疫反应性的轴突膨体含有小圆形小泡（18 - 35纳米）和较大的致密核心小泡（50 - 90纳米）。发现了无髓鞘（0.2 - 0.5微米）和有髓鞘（0.8 - 1.1微米）的血清素样免疫反应性轴突，它们常常散布在类似口径的未标记轴突束中。血清素样免疫反应性的胞体和树突是众多未标记终末的突触后部位，这些未标记终末包含：（a）带有许多小致密核心小泡（30 - 50纳米）的透明圆形小泡（18 - 25纳米），（b）带有大致密核心小泡（90 - 110纳米）的透明圆形小泡（18 - 25纳米），或（c）带有或不带有扁平小泡的透明圆形小泡（18 - 25纳米）。此外，成对的未标记终末在血清素样免疫反应性的树突棘上形成嵴突触。这种与血清素样免疫反应性元件接触的多种未标记终末表明，几个可能具有不同递质的神经元系统可能调节血清素中缝神经元。我们偶尔观察到血清素样免疫反应性的树突和终末与其他血清素样免疫反应性树突并列，在接触部位有膜特化。这可能代表了在中缝背核血清素系统的生理学研究中报道的血清素能神经元自我抑制的一个可能部位。
