ABSTRACT
SUMMARY: The geese's tongue filiform papillae are particularly long, and exhibit the same morphology of a tooth, evoking the lingual teeth of several fishes. In adult animals, they contain numerous mechanical Herbst's corpuscles but no taste buds. In the embryo, they appear since stage 38 and acquire their definitive shape between stages 38 and 42. They express several proteins associated with mammalian tooth development (BMP4, β-catenin, SHH, PITX2, PAX9), also known to be linked to parrot's pseudoteeth and goose's denticulations development. Neurofilaments are early present in the papillae primordia, and appear particularly numerous in adult papillae. Our results suggest that these papillae constitute a mechanical organ with a « tooth shape » derived from ancestral odontodes, whose development is controlled by numerous genes involved in classical odontogenesis.
Las papilas filiformes de la lengua de los gansos son particularmente largas y exhiben la morfología de un diente, evocando los dientes linguales presentes en varios peces. En los animales adultos, contienen numerosos corpúsculos de Herbst mecánicos, aunque una ausencia de papilas gustativas. En el embrión, aparecen a partir del estadio 38 y adquieren su forma definitiva entre los estadios 38 y 42. Expresan varias proteínas asociadas al desarrollo dentario de los mamíferos (BMP4, β-catenina, SHH, PITX2, PAX9), también conocidas por estar asociadas al desarrollo de pseudodientes en el loro y denticulaciones en el ganso. Los neurofilamentos están presentes tempranamente en los primordios de las papilas y aparecen particularmente numerosos en las papilas adultas. Nuestros resultados sugieren que estas papilas constituyen un órgano mecánico con «forma de diente» derivado de odontoides ancestrales, cuyo desarrollo está controlado por numerosos genes implicados en la odontogénesis clásica.
Subject(s)
Animals , Tongue/anatomy & histology , Tongue/metabolism , Geese/anatomy & histology , Tongue/embryology , Immunohistochemistry , Homeodomain Proteins , PAX9 Transcription Factor , Hedgehog Proteins , Bone Morphogenetic Protein 4ABSTRACT
BACKGROUND: The tongue exhibits significant individual variability in terms of shape, color, and surface texture. Due to its location, it is easily accessible for medical examination, although often overlooked. This is due to the inadequate number of studies assessing the morphology of the tongue in the healthy population. Determining the range of normalcy allows for the definition of tongue pathology requiring further diagnostics. The aim of this study is to assess differences in the morphological structure of the tongue in healthy individuals based on existing literature. Morphological structure was evaluated in terms of volume, shape, color, coating, papillae, texture, and lingual tonsil. MATERIALS AND METHODS: PubMed and ResearchGate databases were included for a thorough analysis of morphological differences in tongue structure. RESULTS: Tongue volume stabilizes by the end of the second decade of life and is closely correlated with BMI. Among the shapes of the tongue, forms such as circular, ellipsoidal, hammer-shaped, in the shape of the letter U, V, or W can be distinguished, and the multitude of these terms results from the lack of a uniform classification. There is agreement regarding tongue color, with various shades of pink and white being the most commonly observed, while the presence of another color may indicate disease. The density and size of individual papillae depend on the region of the tongue, age, and the presence of systemic disease. Geographic tongue, hairy black tongue, and fissured tongue are states of papillae pathology. Fissuring of the tongue increases with age, and fissured tongue is more common in men. CONCLUSIONS: Differences in the morphological structure of the tongue provide significant information about the health status of each individual. It is necessary to be aware of the physiological changes occurring within the tongue for proper diagnosis.
ABSTRACT
There are variations in the tongue papillae among species, including the size, number and type of papillae. There have been no studies describing the detailed tongue morphology of Javan mongoose (Herpestes javanicus). Therefore, we analysed the tongue and lingual structures of Javan mongoose (H. javanicus), using scanning electron microscopy and light microscopy. The tongue was covered by papillae and rough in appearance. We divided the tongue into three regions: the apex, corpus and radix of the tongue. The medioventral section of the tongue was characterized by the presence of a frenulum. We identified four types of papillae: filiform, fungiform, conical and vallate papillae. There were two subtypes of filiform papillae: leaf-like and conical. Both were seen on the apex, although leaf-like filiform papillae also extended to the corpus. Fungiform papillae had taste buds on their dorsal surfaces and were observed from the apex to the radix. Vallate papillae, three in numbers only occurred on the radix. Periodic acid-Schiff (PAS) staining showed minor lingual glands on the textus muscularis striatus syncytialis of the corpus and lateral radix, which we identified as Weber glands; we also observed von Ebner glands on this layer of the tongue. These anatomical features of the Javan mongoose tongue are broadly similar to those seen in other carnivores, with some specific differences, such as the number of vallate papillae.
