Microvasculature of the lingual papillae in primates and insectivores--fungiform, vallate and foliate papillae

The red ruffed lemur, Varecia rubra (É. Geoffroy Saint-Hilaire, 1812): a comparative morphology investigation of lingual papillae and connective tissue cores

The morphology of the lingual papillae (filiform, foliate, fungiform, and vallate papillae) and the underlying connective tissue core of the red ruffed lemur (Varecia rubra) of a strepsirrhines species were studied using light and scanning electron microscopy. The filiform papillae distributed at the root of the tongue were larger than the structures distributed at the body and apex. Six to eight vallate papillae were arranged in a Y-shape at the border between the lingual body and the lingual root. Foliate papillae were observed at the posterior lateral border of the tongue. Scanning electron microscopy revealed a primary process and numerous auxiliary processes in the epithelial layer of filiform papillae. After epithelial removal, the connective tissue core of the filiform papilla showed several protrusions surrounding an oval-shaped depression that extended slightly posteriorly, and a large, maple-shaped filiform papilla was seen in the posterior portion of the tongue. The connective tissue cores of the fungiform papillae exhibited a longitudinally ridged cylindrical structure. The connective tissue core of the foliate papillae had numerous tubular projections arranged along a groove with a salivary gland conduit at the base. As a Lemuridae species, the appearance of the fungiform and filiform papillae of the red ruffed lemur is similar to that reported in previous studies of the ring-tailed lemur, with some differences, especially in the filiform papillary connective tissue core at the base and tongue body border. These findings suggest the taxonomic and phylogenetic origins of the lemurs as well as the influence of dietary diversity.

Morphological study of the lingual papillae in the ferret (Mustela putorius furo)

We used four ferrets (Mustela putorius furo) and observed these animals dorsal tongue surface morphology via scanning electron microscope and light microscope. In this investigation, we focused on the food habits and discussed the morphology of the lingual papillae from the viewpoint of comparative anatomy. The ferret has conically-shaped filiform papillae in the posterior, middle and anterior region of the tongue body, and circular-distributed filiform papillae in the lingual apex region. The ferret has fungiform papillae with hemispheric shaped summits in the posterior and middle region with square-shaped summits in the anterior and the lingual apex region. The ferret has V-shaped vallate papillae with eight papillae in two lines or 12 papillae in three lines on the tongue root. No foliate papillae were observed on the dorsal tongue surface of the ferret. The ferret belongs to the carnivore family but has a highly developed vallate papillae which are taste bud papillae and many taste glands. Thus we conclude that the ferrets need a large amount of saliva to swallow food because it demonstrates a large number of taste glands.

Angioarchitecture of the ventral surface of the tongue from Wistar rats

The goal of this study was to describe the angioarchitecture of the ventral surface of the tongue from Wistar rats using a vascular corrosion casting technique associated with scanning electron microscopy (SEM). Six Wistar rats were used for the vascular casting method with Mercox resin. Following the resin polymerization, the tongue of each animal was dissected and corroded in a 5% sodium hydroxide solution. Once the corrosion and drying of the specimens were completed, the specimens were mounted on aluminum stubs, coated with carbon and gold and analyzed under SEM. The results showed that the ventral surface of the tongue presents simple, even and abundant vasculature constituted by a vascular plexus consisting of a superficial vascular network and by the ranine veins. The superficial vascular network, made up of the ascending and descending branches, presents as a loose network, with little morphological variation between the capillary loops.

Angioarchitectural characteristics of the anterodorsal surface of aging and young rabbit tongue: scanning electron microscopy study

The three-dimensional angioarchitecture of young and aging rabbit tongues were studied using a vascular corrosion cast method. The vascular network of different lingual papillae were observed by scanning electron microscope (SEM). Young animals showed filiform papillae distributed all over considered area, with fungiform ones among them. In comparison to developed specimens, young rabbits demonstrated dense and higher organization of microvascular network.