*2.3. Histology*

Sections were stained with toluidine blue. Tissues were deparaffinized (Histoclear; Diamed Inc., Mississauga, ON Canada), rehydrated and stained with 0.1% (w/v) Toluidine Blue O (#198161, Sigma) in 0.25% acid alcohol (HCl) solution. The slides were mounted with Permount™ mounting medium (Fisher Scientific, Montreal, QC, Canada). Sections were observed under bright field microscopy using a Leica LB2 microscope at 400× magnification.
