Ugrumov M V, Popov A P, Vladimirov S V, Kasmambetova S, Novodjilova A P, Tramu G
Laboratory of Hormonal Regulations, Russian Academy of Sciences, Moscow.
Neuroscience. 1994 Jan;58(1):161-5. doi: 10.1016/0306-4522(94)90163-5.
The innervation of the suprachiasmatic nucleus by serotoninergic fibers has been studied in rats from the 22nd embryonic until the 21st postnatal day. The serotoninergic fibers were detected with the pre-embedding immunocytochemical technique at the electron-microscopic level using antibodies to serotonin. Serotonin-immunopositive fibers were always identified as axons as they contained numerous synaptic vesicles both in fetuses and postnatal rats. Moreover, immunopositive dense core vesicles appeared in the axons after birth. From the end of fetal life onwards, the serotonin-immunopositive axons made specialized contacts with the immunonegative neurons, mainly with their dendrites and to a lesser extent with cell bodies and axons. In fetuses, only immature synapses (presynapses) were observed. After birth, presynapses were replaced by typical synapses with the thickened pre- and postsynaptic membranes, accumulations of dense materials at the pre- and postsynaptic membranes as well as with an accumulation of synaptic vesicles at the presynaptic membrane. The functional significance of the serotoninergic input to the suprachiasmatic nucleus in ontogenesis is discussed.
从胚胎第22天到出生后第21天，对大鼠视交叉上核的5-羟色胺能纤维神经支配进行了研究。采用包埋前免疫细胞化学技术，在电子显微镜水平上使用抗5-羟色胺抗体检测5-羟色胺能纤维。5-羟色胺免疫阳性纤维总是被鉴定为轴突，因为在胎儿和出生后的大鼠中它们都含有大量突触小泡。此外，出生后轴突中出现免疫阳性致密核心小泡。从胎儿期结束开始，5-羟色胺免疫阳性轴突与免疫阴性神经元形成特殊接触，主要是与它们的树突接触，与细胞体和轴突接触的程度较小。在胎儿中，仅观察到未成熟突触（突触前成分）。出生后，突触前成分被典型突触取代，突触前膜和突触后膜增厚，突触前膜和突触后膜有致密物质堆积，突触前膜有突触小泡堆积。讨论了5-羟色胺能输入对视交叉上核个体发生的功能意义。
