Objective: To investigate the effect of botulinum toxin-A (BTX-A) on secretion of parasympathetic denervated rabbit submandibular gland.
Methods: Twenty-four rabbits were divided into 3 groups: control (n = 4), parasympathetic denervated submandibular gland (n = 4), and parasympathetic denervated submandibular gland with 5 U BTX-A injection (n = 16). Secretion flow was measured by Schirmer test. Composition of saliva was detected by biochemical method.
Results: Secretion of parasympathetic denervated submandibular gland increased by 139.0% in rest time (P < 0.01), but decreased by 64.2% in feeding time (P < 0.01) compared with controls. Secretion of submandibular gland decreased in rest time 1, 2, 4, and 12 weeks after BTX-A injection compared with that of parasympathetic denervated submandibular gland without injection (P < 0.05), which was also the same in feeding time 1 and 2 week after injection (P < 0.05). The concentrations of amylase, sodium, potassium, chloride and protein of saliva were not changed after BTX-A injection.
Conclusions: BTX-A could decrease the secretion of parasympathetic denervated submandibular gland.