Electrogustometry Thresholds, Tongue Tip Vascularization, Density, and Form of the Fungiform Papillae Following Smoking Cessation.

The objective of this study was to evaluate differences in gustatory function and in shape, density, and vascularization of the fungiform papillae (fPap) of smokers' tongue before and after smoking cessation. In 24 smokers (19 males, 5 females; median age: 54.6 ± 2.9 years) electrogustometry (EGM) thresholds at the chorda tympani area, at the soft palate area and at the area of the vallate papillae were recorded bilaterally. Morphology and density of the fungiform papillae (fPap) and blood vessels' density and morphology at the tip of the tongue were examined using contact endoscopy (CE). Follow-up exams (EGM and CE) were performed on average 3.2 months after smoking cessation. Findings were compared between the 2 conditions as well as to those of a group of 24 non-smokers (median age: 55.2 ± 3.4 years; 19 males, 5 females). After smoking cessation, EGM thresholds decreased significantly (P = 0.02 or P = 0.03 depending on the tested area) but nonetheless still were quite different from those of non-smokers (P = 0.05 or 0.04 depending on the site of EGM measurement). Under CE the fPap density was higher after quitting smoking (P = 0.05) and the shape and vascularization of fPap also exhibited a trend to improvement (P = 0.05) after smoking cessation. Chronic exposure to cigarette smoke infers long lasting, although to a large extent reversible, alterations in morphology of taste buds in fungiform papillae, but rather irreversible EGM-related functional gustatory compromise, suggesting a profound physiologic effect on human peripheral taste organs.

Development of a new method using narrow band imaging for taste assessment.

OBJECTIVES/HYPOTHESIS: The observation of fungiform papillae is a useful objective taste examination. The purpose of this study is to develop a new method using narrow band imaging for assessment of taste function. STUDY DESIGN: Using a narrow band imaging endoscope, we assessed the number and blood vessel morphology of fungiform papillae and compared with the gustatory threshold by the filter paper disc test. METHODS: The number of fungiform papillae was counted in 20 mm(2) , and blood vessels in fungiform papillae were evaluated morphologically by a five-point scoring system in 11 patients who had undergone middle ear surgery. The filter taste disc test was performed simultaneously to obtain the gustatory threshold and was compared with the number and blood vessel morphology of fungiform papillae. RESULTS: Using a narrow band imaging endoscope, we could clearly detect not only fungiform papillae but also blood vessel morphology. There was a significant correlation between the values of the number of papillae and blood vessel morphology. Moreover, these two parameters revealed a significant inverse correlation with gustatory function. As expected, both parameters on the affected side were significant lower than those on the unaffected side in patients. CONCLUSIONS: The assessment of fungiform papillae using narrow band imaging endoscopy is easy, highly sensitive, and reliable; therefore, it might be useful as an objective examination of taste function. LEVEL OF EVIDENCE: N/A.

Age-related changes in electrogustometry thresholds, tongue tip vascularization, density, and form of the fungiform papillae in humans.

The aim of the study was to investigate age-related changes in electrogustometry (EGM) thresholds, in morphology and density of the fungiform papillae (fPap) and in vessels' shape and density at the tip of the human tongue.In 156 nonsmokers (74 males, 82 females; age range: 10-80 years), divided in age groups, EGM thresholds at the chorda tympani area, at the soft palate area, and at the area of the vallate papillae were recorded bilaterally. Morphology and density of the fPap and blood vessels' density and morphology at the tip of the tongue were examined using contact endoscopy (CE). EGM thresholds at the chorda tympani area were significantly higher in both men and women ←60 years of age than in younger individuals. At the soft-palatine area, EGM thresholds were significantly higher in men aged 20-29 years and ←60 years compared with men of other age groups. In women older than 50 years, thresholds at all 3 areas were significantly higher than in the younger age groups. No significant differences in EGM thresholds between the two sexes at all locations tested were detected. The density of fPap decreased significantly in men aged >50 years and in women aged >60 years compared with younger individuals. Vascular density decreased significantly and vascular morphology worsened at the tip of the tongue in subjects older than 60 years of age compared with younger subjects. The study showed statistically significant differences in EGM thresholds between the right and the left side of the tongue and between the two sexes. Aging is associated with a progressive increase in EGM thresholds. Density of fPap plays an important role for taste acuity in females aged >60 years and males aged ←50 years. Morphology of fPap and vessels' density and morphology at the tip of the tongue, as tested by CE, emerge as factors influencing taste function in subjects of both sexes aged >60 years.

Effects of smoking on taste: assessment with contact endoscopy and taste strips.

OBJECTIVES: This study aims to compare the taste function between smokers and nonsmokers with clinical testing, subjective ratings, and contact endoscopy of the tongue. STUDY DESIGN: Cross-sectional survey. METHODS: Data were collected from 38 smokers (mean age 37 years; 25 female, 23 male) and 34 nonsmokers (mean age 33.5 years; 18 female, 16 male). The parameters assessed were the number of fungiform papillae per square centimeter in a noncontact way and their morphology (surface, capillary vessels) by contact endoscopy. The morphology of the filiform papillae has also been assessed. In addition, clinical testing of gustatory function was performed by means of taste strips and subjective intensity ratings of natural taste stimuli. RESULTS: No significant difference was found in clinical testing and intensity ratings between the two study groups. A trend toward significance was found in taste strip results for decreased bitter taste in heavy smokers (P = .06). The number and the size of fungiform papillae did not significantly differ between the study groups. No sex-related differences were observed. Smokers exhibited significantly more keratin structures on the fungiform papillae surface, less tortuous capillary vessels, and a significant distortion of their filiform papillae. CONCLUSIONS: Taste function presents significant resistance to smoking, although changes in morphology of fungiform and filiform papillae have been observed especially in heavy smokers. Laryngoscope, 2010.

Angiogenesis and developmental expression of vascular endothelial growth factor in rat lingual papillae.

We used an embryological approach to investigate development and microvasculature of lingual papillae, and expression of vascular endothelial growth factor (VEGF) in the rat tongue. Temporal changes in the rat tongue at each developmental stage from embryonic day 13 (E13) to postnatal day 7 (P7) were observed by intravascular injection of India ink and immunohistochemistry using a VEGF antibody. At E13, the primordium of circumvallate papilla was observed among various lingual papillae. VEGF was widely expressed at E16 on the proliferated epithelium and the connective tissue core of circumvallate papilla. Invasion by capillary sprouts forming the lingual papillae was observed at E17. The primordium of fungiform papillae was observed at E14. VEGF was strongly expressed around the basal cells of proliferated epithelial tissues of fungiform papillae at E17. At E18, blind-ended capillary sprouts invaded into connective tissue cores from subepithelial sinusoidal capillaries by sprout angiogenesis. At P1, the invading capillary sprouts formed loops by vascular remodeling. The primordium of foliate papillae was observed at E16. VEGF was slightly expressed, but uniformly at E17 on the epithelium, muscle cells, and fibroblasts of foliate papillae. At E18, vascular density was increased by angiogenesis. The primordium of filiform papillae was observed at E17. It was the last to develop among the lingual papillae. VEGF was expressed in the cytoplasm of grown epithelial cells of filiform papillae at E19, and in blind-ended capillary sprouts formed by angiogenesis in the connective tissue cores at E20. The capillary sprouts formed loops by vascular remodeling at P1. Consequently, VEGF was expressed on the papillary epithelium and connective tissue cores of papillae during development of the papillary epithelium, and invasion by capillary sprouts into each papillae was observed thereafter. These results suggest a close relationship between expression of VEGF and angiogenesis of lingual papillae in the rat.

Observation of tongue papillae by video microscopy and contact endoscopy to investigate their correlation with taste function.

OBJECTIVES: Contact endoscopy is a technique used to obtain detailed images of living epithelium in the fields of gynecology, rhinology and laryngology. Video microscopy is useful for observation of the surface of tongue papillae. In the present study, we attempted to apply the contact endoscopy technique together with video microscopy to observe tongue papillae, and to study the correlation between the condition of fungiform papillae and taste function. METHODS: Ten subjects (3 men, 7 women) were divided into two groups based on the results of a taste examination by electrogustometry. We compared the shape and blood vessels of the papillae between normal taste and taste disorder groups. RESULTS: In the normal taste group, round shaped papillae and clear blood vessels were observed with both microscopy and contact endoscopy. In the taste disorder group, flat and irregular papillae were observed with microscopy. Blood vessel flow of the papillae was observed to be poor with contact endoscopy. CONCLUSION: These findings suggested that the images of microscopy and contact endoscopy were related to taste function, and both techniques were useful for evaluating taste function.

Angioarchitectural arrangements in corrosion casts of the tongue of young malnourished rats

Casts of the microvascular of three types of lingual papillae have been investigated by scanning electron microscopy (SEM) employing the corrosive resin cast technique. The microvascular arrangements of the filiform papillae exhibit both a simple and a twisted capillary loops. The fungiform papillae which are formed by capillary network resembles a cylinder with a central hole on it. At a high magnification, the venulaeexhibit nuclear imprint of the endothelial cells. The data presented in this study show the general arrangement and angioarchitecture of the lingual papillae in rats on a protein-free diet.

Microvasculature of the dorsum of the rat tongue: a scanning electron microscopic study using corrosion casts.

The purpose of this study was to examine the microvascular system of the dorsum of the rat tongue in relation to the subepithelial connective tissue relief. Methylmethacrylate corrosion casts of the vasculature as well as specimens in which the epithelium had been removed were prepared and examined by scanning electron microscopy (SEM). The SEM images revealed four distinct layers in the vasculature of the lamina propria. Superficially, Layer 1 comprised the irregularly shaped ends of capillary loops. Layer 2 consisted of parallel ascending and descending capillaries. These two layers were drained by the subjacent Layer 3, a fish-net-like venous plexus. More deeply, Layer 4 contained arterioles ascending from the muscular layers of the tongue. The vessels of larger papillary structures formed cylindric networks supplied by several arterioles and drained through a single venule to the venous plexus in Layer 3. At their base, the capillary loops often showed a constriction, suggestive of a sphincter. Arteriovenous anastomoses were rare. The epithelium-connective tissue interface showed short conical papillae as well as larger papillary structures which corresponded in both distribution and size to the capillary loops found in the vascular casts. The results confirm that the tongue is highly vascularized and demonstrate that the vascular supply to the papillae, taste buds, and other surface structures forms a highly organized and specific system which is adapted to the specific functions of this organ in the rat.

The blood circulation of the tongue.

This article describes the gross anatomy of the vessels which supply the mammalian tongue. It shows that there is a rich vascular supply. Available data indicate that the lingual papillae are supplied with a true capillary circulation, which is more abundant in the papillae containing taste buds. The vessels of the tongue are innervated by adrenergic sympathetic vasconstrictor fibers and it is also very likely that a cholinergic parasympathetic vasodilator influence exists.

Catecholamine-containing cells of the taste buds in the tongue of the frog (Rana temporaria).

In a study of the epithelial layer and taste buds of the tongue of the frog using fluorescence, peculiar dumb-bell shaped cells were found in the taste buds of fungiform papillae and these showed a highly-positive reaction to catecholamines. Adrenergic nerve fibres were detected in the vessels of the taste bud and in the epithelium of the tongue. Under conditions of catecholamine deficiency produced by preliminary reserpinization of frogs a decrease in specific fluorescence of the cells and the nerves was observed.