Fig. 1From: Apoptotic action of botulinum toxin on masseter muscle in rats: early and late changes in the expression of molecular markersThe results of the TUNEL assay at 2 weeks after injection. a The number of highly fluorescent nuclei in the masseter muscle was increased in the 5 U and 10 U BTX-A-treated groups in comparison to the saline-treated control group (original magnification ×400). DAPI staining was used as a counterstaining. b The TUNEL assay demonstrated that the number of TUNEL-positive nuclei was significantly higher in the 10 U BTX-A-treated group than in the saline-treated group (*P < 0.001)Back to article page