Kafitz K W, Güttinger H R, Müller C M
Abteilung für Allgemeine Zoologie, Universität Kaiserslautern, Germany.
Glia. 1999 Jul;27(1):88-100.
In the song control area HVc of the canary, intercellular dye-coupling among astrocytes was studied by intracellular injection of neurobiotin into identified single astrocytes. Injection of individual astrocytes into acute slices resulted in dye spread to neighboring astrocytes, covering a sphere of up to 1 mm in diameter. The astrocytic nature of the dye-coupled cells was verified by double labeling of neurobiotin-filled cells with antisera for the astrocytic filament proteins GFAP or vimentin. The similarity in the number of dye-coupled cells and the total number of astrocytes labeled by immunocytochemical markers indicate that dye-coupling is specific for astrocytes and labels almost the entire local astrocytic population. Within the major nucleus for vocal control (HVc), approximately 25% more astroglial cells were present than in the surrounding forebrain tissue. There is no apparent hindrance of dye spread at the border of the HVc. The density of dye-coupled astrocytes and the expression of cytoskeletal filament proteins differed markedly between the reproductive period in spring and the quiescent period in autumn. While vimentin is the major astroglial filament in autumn, GFAP is strongly expressed in spring. The density of dye-coupled astrocytes reveals a marked increase in the reproductive period, followed by a reduction in autumn. The data indicate that the astrocytic population in the avian forebrain undergoes significant changes coincident with the known functional changes in the vocal control nuclei during periods of song production.
在金丝雀的歌曲控制区域HVC中，通过向单个已识别的星形胶质细胞内注射神经生物素，研究了星形胶质细胞之间的细胞间染料偶联。将单个星形胶质细胞注射到急性切片中会导致染料扩散到相邻的星形胶质细胞，覆盖直径达1毫米的球体。通过用星形胶质细胞丝状蛋白GFAP或波形蛋白的抗血清对充满神经生物素的细胞进行双重标记，验证了染料偶联细胞的星形胶质细胞性质。染料偶联细胞的数量与免疫细胞化学标记物标记的星形胶质细胞总数的相似性表明，染料偶联对星形胶质细胞具有特异性，并且标记了几乎整个局部星形胶质细胞群体。在主要的发声控制核（HVC）内，星形胶质细胞的数量比周围的前脑组织中大约多25%。在HVC边界处，染料扩散没有明显障碍。在春季繁殖期和秋季静止期之间，染料偶联星形胶质细胞的密度和细胞骨架丝状蛋白的表达有明显差异。虽然波形蛋白是秋季主要的星形胶质细胞丝，但GFAP在春季强烈表达。染料偶联星形胶质细胞的密度显示在繁殖期显著增加，随后在秋季减少。数据表明，在发声产生期间，鸟类前脑的星形胶质细胞群体发生了与已知的发声控制核功能变化相一致的显著变化。
