A型肉毒毒素对大鼠下颌下腺作用的形态学及免疫组织化学研究

目的 :研究大鼠下颌下腺局部注射A型肉毒毒素 (BTX A)后不同时间形态学改变及对P物质 (SP)表达的影响。方法 :实验用 18只雌性Wistar大鼠 ,采用右侧下颌下腺注射BTX A模型 ,分别于用药后 6d、10d、30d处死动物 ,用组织形态学及免疫组织化学染色方法 ,观察BTX A作用不同时间下颌下腺组织形态学改变以及对SP表达的影响。左侧注射生理盐水作为对照组。结果 :大鼠注射BTX A不同时间下颌下腺中腺泡及腺管细胞形态发生改变。注射BTX A 6d后 ,腺泡细胞出现萎缩 ,以 10d组最明显 ,可见大量腺泡细胞萎缩 ,30d组萎缩的腺泡细胞量减少。各时间组萎缩的腺泡周围未见炎症细胞浸润及坏死发生。免疫组织化学结果显示 ,6d组BTX A注射侧腺泡周围SP免疫反应阳性纤维减少 ,与对照侧相比差异有统计学意义 (t =- 3.4 92 ,P <0 .0 5 )。 10d组BTX A注射侧腺泡周围SP免疫反应阳性纤维明显减少 ,与对照侧相比差异有统计学意义 (t=- 9.70 7,P <0 .0 1)。 30d组BTX A注射侧与对照侧SP免疫反应阳性纤维染色密度基本相同 (t =- 1.185 ,P>0 .0 5 )。结论 :大鼠下颌下腺注射BTX A可以导致腺泡及腺管细胞暂时性萎缩 ,SP表达暂时性减少 ,说明其可能通过这两方面共同作用而达到治疗多涎症的目的。

Immunohistochemical and morphological investigations of the influence of botulinum toxin type A on the submandibular gland of the rats

OBJECTIVE: The morphological changes and the expression of substance P of BTX-A effected on the submandibular gland of the rat were investigated in the study. METHOD: A total of 18 female Wistar rats were used. BTX-A was injected at right side submandibular gland. All the animals were sacrificed at the 6th day, 10th day and 30th day after treatment. Using morphological and SABC immunohistochemical methods to observe the changes of cell morphology and the expression of substance P after local applications of BTX-A at different times. The left gland was injected with physiological saline as control. RESULT: The morphology of acinar cells and ducts were different after BTX-A injection at observed time points. At the 6th day after BTX-A injection, acinar cells began to atrophy. Especially to the 10th day after treatment, lots of acinar cells and gland ducts showed atrophy. At the 30th day, few atrophic acinar cell was observed which was as same as control side. There were no cellular infiltration and necrosis around the acinar cells and ducts in all groups. Immunohistochemical study revealed that the density of substance P immunoreactive (SP-IR) fibers lowered at the 6th day after BTX-A injection. A marked decrease of SP-IR fibers was shown at the 10th day after BTX-A application. There was significant difference vs control side (P<0.01). However, the expression of SP-IR increased at the 30th day, which was similar to control side. CONCLUSION: It has been shown that BTX-A induced temporarily atrophy of acinar cells and ducts in rats submandibular gland and reduced the expression of substance P temporarily. The results suggested that local BTX-A treatment was a selective method to treat the hypersalivation.