Schaffar N, Jean A, Calas A
Neurosci Lett. 1984 Jan 27;44(1):31-6. doi: 10.1016/0304-3940(84)90216-7.
Serotonin (5-HT) axon terminals were demonstrated in the rat trigeminal motor nucleus (VmN) using radioautography following local injection of tritiated 5-HT. The light microscope radioautographs of the VmN showed silver grain aggregates typical of axonal varicosities having taken up the exogenous 5-HT. In electron microscope radioautographs, labeled 5-HT axon terminals took the form of unmyelinated enlargements, 0.3-2 micron in diameter (average 0.9 micron) containing small clear and large granular vesicles. Out of 182 labeled 5-HT profiles, only 4.9% showed a clear synaptic junction with dendritic branches, indicating the existence of non-synaptic as well as synaptic mechanisms for the 5-HT terminals within the VmN. An estimate of the density of 5-HT varicosities within the VmN was performed on histological radioautographs: the concentration of labeled terminals was evaluated at (1.8 +/- 0.38) X 10(6) per mm3.
在局部注射氚标记的5-羟色胺（5-HT）后，采用放射自显影法在大鼠三叉神经运动核（VmN）中显示5-羟色胺（5-HT）轴突终末。VmN的光学显微镜放射自显影片显示，摄取了外源性5-HT的轴突膨体呈现典型的银粒聚集。在电子显微镜放射自显影片中，标记的5-HT轴突终末呈无髓鞘膨大形式，直径为0.3 - 2微米（平均0.9微米），含有小清亮囊泡和大颗粒囊泡。在182个标记的5-HT形态中，只有4.9%显示与树突分支有清晰的突触连接，这表明VmN内5-HT终末存在非突触和突触机制。在组织学放射自显影片上对VmN内5-HT膨体的密度进行了估计：标记终末的浓度评估为每立方毫米（1.8 ± 0.38）× 10⁶ 个。
