Histopathological and radiological investigations of the influence of botulinum toxin on the submandibular gland of the rat.

The aim of the study was to correlate the sonographic features of Botox A injection in rat submandibular gland with the histopathological changes. Fifteen Wistar albino rats were randomly assigned to 2 groups. Group 1 (control group) consisted of 5 animals not given any substance. Group 2 was divided as "a" and "b" each consisting of 5 animals. A median cervical incision has been performed to the rats in group 2 and 2.5 U Botulinum toxin A reconstituted 0.1 ml physiologic saline was injected into the right gland. Sonograms were obtained before the application, at the first day of the Botox A application, in addition to group 2a on the 14th day, and on 28th day to group 2b. Gland size was lower in group 2a and 2b comparing to control group. The gland size of group 2b was lower than group 2a. There was no change in vascularization. There was no other histopathological change except lymphocytic infiltration in group 2. It was observed that Botox A injection does not have a direct effect on the cells in submandibular gland but it causes a homogenic shrinking in gland size without atrophy.