For histological analysis, the surrounding tissues were fixed in 10% (v/v) formalin overnight. After fixation, the tissues were washed in running tap water for 24 h. Afterward, it was dehydrated in graded alcohols, cleared in xylene, and embedded in paraffin. 4 μm sections were taken from paraffin blocks with the help of a Leica RM2145 microtome. The slides were then stained for hematoxylin and eosin (H&E) staining (Sigma) according to the manufacturer´s instructions. The examinations were carried out under the Olympus U-TV0.63XC microscope (Japan).