Ação da toxina botulínica tipo A no complexo submandibular-sublingual de ratos : estudo morfológico, micológico, bioquímico e toxicológico

Abstract

Intraglandular injection of botulinum toxin type A (BTX-A) into the submandibular glands is clinically considered an effective therapeutic tool for the treatment of sialorrhoea. However, there are few data in the literature that discuss its influence on the glandular tissue, oral saliva and microbiota, as well as its systemic metabolism. Thus, the objective of the present study was to measure salivary and serum serum electrolytes, to verify the salivary proteins, to perform the mycological diagnosis of the oral cavity of rats and their profile of sensitivity in vitro to antifungals, to analyze the serum biochemistry, to proceed with the histopathological study of the livers and kidneys, in addition to observing the presence of apoptosis through the TUNEL technique and the histological characteristics of the submandibular-sublingual complex parenchyma of rats treated with BTX-A intraglandular injection. Wistar rats were divided into five groups: control group (n = 7), without any treatments; BTX-A groups 12 days (n = 7) and 35 days (n = 6), whose submandibular glands of the right submandibular-sublingual complexes received 2.5 U BTX-A (Prosigne®), with samples analyzed 12 and 35 days after application; and GEL groups 12 and 35 days (n = 6 animals each), whose right salivary glands received injection of 0.125 mg gelatin of bovine origin, with parameters analyzed 12 and 35 days after treatment, respectively. The data collected were submitted to statistical analysis. BTX-A promoted atrophy of serous acyles with cytoplasmic vacuolations. The appearance of apoptosis was most evident in the BTX-A treated groups and analyzed at 12 days. The lymph nodes of the BTX-A treated groups showed reactivity. There were few changes in salivary proteins and ions. Fungi of the genres Candida spp. and Aspergillus spp., Behaved as opportunists in the groups treated with BTX-A, besides being resistant to the antifungal agents tested. Histopathological alterations in the kidneys were verified, but without hepatic alterations.