Gemryd P, Norberg L E, Lundquist P G
Department of Otolaryngology, Head and Neck Surgery, Linköping University Hospital, Sweden.
ORL J Otorhinolaryngol Relat Spec. 1992;54(1):33-7. doi: 10.1159/000276256.
The degranulation and regranulation process was investigated after alpha-adrenergic stimulation on the rat submandibular gland. The submandibular gland in rat contains both serous and mucous cells. It has earlier been shown that serous cells filled with heavy-metal granules, are markedly more radiosensitive than cells without granules. In experiments with emptying the serous cell of their content of granules by administering an alpha-adrenergic stimulant, cyclocytidine, there has been found a decrease in irradiation damage in salivary gland tissue after irradiation. Injection of cyclocytidine, 150 mg/kg, was given i.p. to the rat. After 1 h there was almost complete depletion of granules in the serous cells, no morphological aberration was seen in the mucous cells. This effect still remained after 6 h. A beginning of regranulation with apical granules was seen 12 h after injection. After 24 h an almost complete regranulation had occurred in the salivary gland serous cells. The mucous cells did not show any morphological aberration. Our intent is to reduce unwanted salivary gland damage in patients with head and neck cancer when treated with radiotherapy. Depletion of heavy-metal granules in serous cells, before irradiation may diminish morphological destruction in the salivary glands. As a nearly total degranulation is present between 1-6 h after stimulation, this should be the optimal time for radiotherapy.
在对大鼠下颌下腺进行α-肾上腺素能刺激后，研究了其脱颗粒和再颗粒化过程。大鼠的下颌下腺包含浆液性细胞和黏液性细胞。此前已有研究表明，充满重金属颗粒的浆液性细胞比无颗粒的细胞对辐射明显更敏感。在用α-肾上腺素能兴奋剂环胞苷使浆液性细胞排空其颗粒内容物的实验中，发现照射后唾液腺组织的辐射损伤有所减少。给大鼠腹腔注射150mg/kg的环胞苷。1小时后，浆液性细胞中的颗粒几乎完全耗尽，黏液性细胞未见形态学异常。6小时后这种效应仍然存在。注射后12小时可见顶端颗粒开始再颗粒化。24小时后，唾液腺浆液性细胞几乎完全再颗粒化。黏液性细胞未见任何形态学异常。我们的目的是减少头颈部癌患者在接受放射治疗时唾液腺的不必要损伤。照射前使浆液性细胞中的重金属颗粒耗尽可能会减少唾液腺的形态破坏。由于刺激后1 - 6小时存在几乎完全的脱颗粒，这应该是放射治疗的最佳时间。
