The Three-Dimensional Characteristic of Fungiform Papillae and its Taste Buds in European Bison (Bison Bonasus), Cattle (Bos Taurus), and Bison Bonasus Hybrid

Background: Our recent macro- and scanning electron microscopic study of tongue and lingual papillae conducted on domesticated cattle, wild living European bison, and its Bison bonasus hybrid revealed the presence of morphologic differences between parental species and the hybrid. Analysis of gustatory papillae indicated the variable distribution of fungiform papillae (Fu) on the dorsal and ventral surface of the apex and body of the tongue to be important in taste perception during feeding and in the discussion concerning differentiated diet and living environments of studied ruminants. To specify detailed macro-and microstructure of Fu papillae, and its connective tissue cores (CTC) and taste buds, we have chosen for the first time the three-dimensional computer-aided analysis of serial histoslides resulted in the rendering of 3D reconstructions of Fu papillae, which allowed also determine the histomorphometric characteristic of studied papillae. Results and conclusions:For comparative analysis of 3D models of Fu papillae and taste buds were taken from six areas of each tongue provided data about the diversity of Fu papillae in studied ruminants. The calculations of the number and density of Fu papillae of the tongues allowed us to distinguish the ventral surface of the lingual apex and posterolateral surfaces of the lingual torus as two regions important in taste perception, i.e., in the preselection of taken food and analysis of food during rumination, respectively. For the first time were indicated differences in grade of protrusion of Fu papillae over the tongue surface, the presence of three structural types of CTC, and the exact number of taste buds per papilla. The quantitative data of the number of taste buds expanded the knowledge about regional differences of the taste system. Moreover, 3D imaging resulted in the first description of variable patterns of distribution of taste buds over the surface of each Fu papillae. The comparison of obtained results determined new species-specific features in examined hybridand its similarities of some features with cattle, i.e., maternal species. The 3D reconstruction method proved to be an innovative and efficient tool in evaluating microstructures of Fu papillae, and it could be a suitable tool for further studies of gustatory papillae and taste buds in mammals.

ALTERATION OF TASTE BUDS IN EXPERIMENTAL CIRRHOSIS. Is there correlation with human hypogeusia?

ABSTRACT Background The inherent complications of cirrhosis include protein-calorie malnutrition and micronutrient deficiencies.Changes in taste are detrimental to the nutritional status, and the mechanism to explain these changes is not well documented in the cirrhotic patients. Objective To evaluate the taste buds of cirrhotic rats. Methods Fourteen male Wistar rats were evaluated. After 16 weeks, the liver was removed to histologically diagnose cirrhosis, and blood was collected to perform liver integrity tests. The tongue was removed for histological examination and immunohistochemistry using antibodies against protein gene product PGP 9.5 and the sweet taste receptors T1R2 and T1R3. Morphological changes were determined by scanning electron microscopy. Serum zinc levels were measured. Results The cirrhotic animals, but not the control animals, exhibited zinc deficiency. In both groups, there was positive immunoreactivity for type II and III cells and T1R2 receptors. The cirrhotic animals had no immunoreactivity for T1R3 receptors. Scanning electron microscopy analysis of the cirrhotic group revealed a uniform tapering of the gustatory papillae. Conclusion In conclusion the experimental cirrhosis model mimicked the biochemical and histological parameters of human cirrhosis, therefore enabling a study of the gustatory papillae and taste buds.

ANATOMICAL STUDY OF THE TONGUE OF INDIGENOUS COW (BOS INDICUS) IN BANGLADESH WITH SPECIAL EMPHASIS ON PAPILLAE DISTRIBUTION

The present study was conducted on the tongue of six apparently healthy indigenous (Bos indicus) cows of different age and sex and they were collected from local market at Dinajpur district and this research work was conducted in the Department of Anatomy and Histology, Dinajpur Government Veterinary College, Dinajpur during the research period from the month of July 2003 to April 2004. After proper euthanasia, the animals were killed and then the tongues of these animals were dissected out from the carcasses and fixed in 10% neutral buffered formalin solution. In the present study it was observed that the tongue of indigenous cow (Bos indicus) of Bangladesh has three parts: the root, body and an apex. The dorsum linguae was specially more pronounced in its centre and was occupied by numerous types of masticatory and gustatory papillae. The fine rasp-like filiform papillae were more numerous and directed caudally throughout the dorsum and packed closely in front of the fossa linguae throughout the tip, whereas, the club shaped fungi form papillae were irregularly distributed all over the dorsum among the filiform papillae. The broad headed lentil shaped lenticular papillae was also found in the rostral two-thirds of the dorsum but better developed along the mid-line of the tongue. The large conical papillae of the tongue of Bos indicus occurred in the rostral two-thirds of the dorsum with a higher concentration in the middle portion of the tongue, however, the small ones occurred through out the torus. The vallate papillae of the tongue of Bos indicus were 12-20 in number on either side and dispersed in two irregular rows (25-40) in total along the caudolateral two-thirds of the dorsum. The mucosa of the root of the tongue of Bos indicus did not show any specific papillae but it was rather smooth due to diffused lymphoid tissue distribution (lingual tonsil).