Expression of Ki67 in submandibular salivary glands of rabbits after BTX injection: Histological and immunohistochemical study

Abstract

This study aimed to examine the possible histological effects of local injections of BTX in rabbits submandibular SGs and to find the dose-dependent and time relationship between injections and study immunohistochemistry expression of Ki67. Thirty male rabbits randomly divided into 3 groups (10 rabbits for Each) 1st group: control (without treatment), 2nd group treated with 5U of BTX and 3rd group treated with 10U of BTX, five animals of each group were sacrificed in 1st week of treatment and another five animals sacrificed in 4th week of treatment. The rabbit was anesthetized then injected with the BTX in the gland. The histopathological changes in Group 5, 10 Unit BTX (1st week) were vacuolar degeneration of mucous acini cells, degeneration of serous acini cells, while the lesions showed hyperplasia and necrosis of epithelial cells lining striated ducts, necrosis of serous acini epithelium. The Diameter of mucous acini were found to be significantly increased in 10 Unit BTX groups. During the 1st and 4th weeks, the surface area of the striated ducts in the 5- and 10-unit BTX groups increased significantly, and the number of striated ducts in the 10 Unit BTX group decreased significantly when compared to the 1st week period of the same group. BTX groups revealed moderate to weak positive cytoplasmic reactivity for Ki67 protein in the parenchymal tissue of the glands. We conclude that BTX causes histological changes in the salivary gland as well as affecting Ki67. This data could be used in a future study to investigate the usage of BTX in cancer treatment.