Otolaryngology & Head and Neck Center, Cancer Center, Department of Otolaryngology, Zhejiang Provincial People's Hospital (Affiliated People's Hospital, Hangzhou Medical College), Hangzhou.
Department of Otorhinolaryngology-Head and Neck Surgery, Zhongda Hospital, Southeast University, Nanjing.
Eur J Histochem. 2024 Nov 6;68(4):4137. doi: 10.4081/ejh.2024.4137.
This study investigated the expression of calretinin (CR) in the mouse cochlea from embryonic day 17 (E17) to adulthood through immunofluorescence. At E17, CR immunoreactivity was only detected in the inner hair cells (IHCs). At E19, the IHCs and spiral ganglion neurons (SGNs) begin to express CR. At birth, CR immunoreactivity was confined primarily to the IHCs and the majority of the SGNs, as identified by TUJ1, both the cytoplasm and the nucleus of SGNs exhibited CR positivity. At postnatal day 2 (P2), auditory nerve fibers reaching the IHCs were stained for CR. CR continued to be expressed in the IHCs, whereas only single row of outer hair cells (OHCs) were positive for CR. By P5, CR expression was evident in IHCs and the three rows of OHCs, with SGNs soma and their neurite projections also displaying CR immunoreactivity. From P8 through adulthood, CR expression persisted in the SGNs and their afferent neurite projections to the IHCs, as well as in IHCs and OHCs. Dual labeling of CR with afferent nerve marker neurofilament 200 (NF200) demonstrated that NF 200-positive SGN somas were encompassed by CR-labeled plasma membrane of SGNs, and NF 200 was co-localized with CR in the afferent nerve fibers innervating the IHCs. We also described the expression of peripherin, a marker for type II SGNs, in the mouse cochlea at various postnatal stages. Peripherin showed a distinct spatio-temporal expression compared to CR in auditory nerve fibers. No co-expression of peripherin and CR was detected in adult. Dynamic expression patterns of CR in the embryonic and postnatal cochlea supported its roles in cochlear development.
本研究通过免疫荧光法研究了 calretinin（CR）在小鼠耳蜗中的表达，从胚胎第 17 天（E17）到成年期。在 E17 时，仅在内耳毛细胞（IHC）中检测到 CR 免疫反应性。在 E19 时，IHC 和螺旋神经节神经元（SGN）开始表达 CR。出生时，CR 免疫反应性主要局限于 IHC 和大多数 TUJ1 鉴定的 SGN，SGN 的细胞质和细胞核均呈 CR 阳性。在出生后第 2 天（P2），到达 IHC 的听神经纤维被 CR 染色。CR 继续在 IHC 中表达，而仅有外毛细胞（OHC）的单一排呈 CR 阳性。在 P5 时，CR 在 IHC 和三排 OHC 中表达明显，SGN 体和其神经突投射也显示出 CR 免疫反应性。从 P8 到成年，CR 在 SGN 及其向 IHC 的传入神经突投射以及 IHC 和 OHC 中持续表达。CR 与传入神经标志物神经丝 200（NF200）的双重标记表明，NF200 阳性 SGN 体被 SGN 标记的质膜所包围，NF200 与支配 IHC 的传入神经纤维中的 CR 共定位。我们还描述了在各种出生后阶段，鼠耳蜗中 II 型 SGN 标志物 peripherin 的表达。与听觉神经纤维中的 CR 相比，peripherin 表现出明显的时空表达。在成年时未检测到 peripherin 和 CR 的共表达。CR 在胚胎和出生后耳蜗中的动态表达模式支持其在耳蜗发育中的作用。
