Garrosa M, Coca S
Department of Cell Biology, Faculty of Medicine, University of Valladolid, Spain.
J Morphol. 1991 Jun;208(3):257-69. doi: 10.1002/jmor.1052080303.
Three basic types of cells are distinguished in the rat vomeronasal epithelium at birth: bipolar neurons, supporting cells, and basal cells. Neurons at this time include both immature and differentiated cells. By the end of the first postnatal week, all neurons show morphological signs of maturity in their cytoplasm, including abundant granular and smooth endoplasmic reticulum, neurotubules, dense lamellar bodies, apical centrioles, and tufts of microvilli. During the third week microvilli are more frequently encountered and appear to be longer and more branched. Supporting cells appear well-developed by the second day after birth. During the first ten days of life, supporting cells lose their centrioles and all of the complex associated with ciliary generation in the apical zone. Basal cells appear to be more numerous in newborns than in older animals. Protrusions projecting into the lumen are frequently observed in the epithelium of newborn animals, both on the dendrites of neurons and on supporting cells. After the third week, such protrusions are only observed in the transitional zone between the sensory and the non-sensory epithelia of the vomeronasal tubes. In this transitional zone, a fourth cell type showing apical protrusions with microvilli differentiates. Cytoplasm in this type resembles that of neighboring ciliated cells but has no cilia or centrioles. These transitional cells are considered to be cells in an intermediate state of differentiation, between that of the differentiated neurons and supporting cells of the sensory epithelium and that of the predominate ciliated cells of the non-sensory epithelium. The results suggest that by the end of the third week the vomeronasal epithelium is morphologically mature.
出生时，大鼠犁鼻器上皮细胞可分为三种基本类型：双极神经元、支持细胞和基底细胞。此时的神经元包括未成熟和已分化的细胞。出生后第一周结束时，所有神经元的细胞质都显示出成熟的形态学特征，包括丰富的颗粒状和平滑内质网、神经微管、致密板层小体、顶端中心粒和微绒毛束。在第三周，微绒毛更常见，且似乎更长、分支更多。支持细胞在出生后第二天就发育良好。在出生后的前十天，支持细胞失去了它们的中心粒以及顶端区域中与纤毛生成相关的所有复合体。新生动物的基底细胞似乎比成年动物更多。在新生动物的上皮中，无论是在神经元的树突上还是在支持细胞上，都经常观察到向管腔突出的突起。第三周后，这种突起仅在犁鼻管感觉上皮和非感觉上皮之间的过渡区域中观察到。在这个过渡区域，一种显示顶端有微绒毛突起的第四种细胞类型开始分化。这种类型的细胞细胞质与相邻的纤毛细胞相似，但没有纤毛或中心粒。这些过渡细胞被认为是处于分化中间状态的细胞，介于感觉上皮的分化神经元和支持细胞与非感觉上皮的主要纤毛细胞之间。结果表明，到第三周结束时，犁鼻器上皮在形态上已成熟。
