Ganchrow J R, Ganchrow D
Department of Oral Biology, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel.
Anat Rec. 1989 Nov;225(3):224-31. doi: 10.1002/ar.1092250308.
Recent evidence from mature hamster fungiform papillae indicates that following denervation taste buds are present from 21 to 330 days in the absence of discernible intragemmal nerve fibers. In contrast, most prior taste bud degeneration studies focused on shorter survival times. The present inquiry in young rats examined the issue of postneurectomy buds, in which regeneration of the resected chorda tympani or facial nerves was prevented and anterior tongue tissue examined over a range of relatively long survival times (30-90 days). Conditions for observing potential taste buds used three histologic stains and a definition of the taste bud not necessarily requiring pore identification. In each case, serial section examination of the anterior-most 2-3 mm of lingual epithelium revealed 29-56 bud-containing fungiform papillae on the unoperated side. In contrast, ipsilateral to the neurectomy, only zero-7 medially-placed, mature-looking buds were observed per case, as well as zero-3 more laterally situated fungiform papillae containing small clusters of cells in basal epithelium that lacked the vertical organization and cytoplasmic staining intensity of mature taste buds. These cell aggregates were distributed evenly across survival time and stain used. Therefore, in young rats following gustatory neurectomy, longer survival times, per se, would not appear to be a prerequisite for sustaining fungiform taste buds. The appearance of "midline" buds postsurgery may be attributed to either normal contralateral or a net bilateral innervation, and/or ipsilateral denervation and bud loss inducing neural sprouting from the contralateral side.
来自成熟仓鼠菌状乳头的最新证据表明，去神经支配后，在没有可辨别的味蕾内神经纤维的情况下，味蕾可存在21至330天。相比之下，大多数先前的味蕾退化研究集中在较短的存活时间。本研究在幼鼠中探讨了神经切除后味蕾的问题，其中切除的鼓索神经或面神经的再生被阻止，并在一系列相对较长的存活时间（30 - 90天）内检查了舌前部组织。观察潜在味蕾的条件使用了三种组织学染色方法，并且对味蕾的定义不一定需要识别小孔。在每种情况下，对舌上皮最前端2 - 3毫米进行连续切片检查，发现在未手术侧有29 - 56个含有味蕾的菌状乳头。相比之下，在神经切除同侧，每例仅观察到0 - 7个位于内侧、外观成熟的味蕾，以及0 - 3个位于外侧的菌状乳头，其基底上皮中有小细胞簇，缺乏成熟味蕾的垂直组织结构和细胞质染色强度。这些细胞聚集体在存活时间和使用的染色方法中分布均匀。因此，在幼鼠味觉神经切除后，较长的存活时间本身似乎不是维持菌状味蕾的先决条件。手术后“中线”味蕾的出现可能归因于正常的对侧或双侧神经支配，和/或同侧去神经支配和味蕾丧失导致对侧神经发芽。
