Taste Buds In Foliate Papillae Research Articles

Morphological and functional comparison of lingual papillae in suckling and adult feral cats: Forensic evidence.

Feral cats are considered as strays and are more likely to hunt in the street. We investigated the effect of environmental adaptations on the structures of lingual papillae in feral cats, which could be used as forensic evidence for their identification. There are no reported studies about the structural comparison of lingual papillae between suckling and adult feral cats. The present study described the lingual papillae of both suckling and adult cats macroscopically and microscopically via light and scanning electron microscopy. A total of nine tongue samples each for suckling and adult feral cats were examined grossly and histologically. Papillae distributions of suckling cats were similar to those observed in adult cats. Meanwhile, the shapes of those papillae were markedly different from that of corresponding papillae in adults. The change in taste bud position and size seemed to be related to the progressive growth of the papillae between adult and suckling cats; absence of taste buds in foliate papillae of feral cats at any stage; and marginal papillae which were a characteristic feature for all suckling cats. All previous elements could be affected by the specific feeding behaviour and mastication mode adaptation in suckling and adult feral cats which might help to identify suckling and adult feral cats among other breeds and animal species. We anticipate these findings may provide promising forensic evidence to discriminate between adult and suckling feral cat remains as well as prediction of environmental harshness and feeding behaviour.

Streptozotocin 誘発糖尿病ラットの味蕾の電子顕微鏡的研究

Diabetic dysgeusia has been revealed since the first Fox's report (1932). In diabetes mellitus, however, ultrastructural study of the taste buds has not reported yet. In this point of view, the present study was perfomed to investigate morphological changes of the taste buds in foliate papillae in streptozotocin (STZ) induced diabetic rats. Diabetes was induced by intra abdominal injection of STZ (60 mg/kg b. w.). After raising for 3 months, 6 months and 12 months, the foliate papillae were collected and observed by means of electron microscopy. The results were as follows : 1. The taste buds of STZ rats were characterized by swelling cytoplasm, vacuole formation, and enlarged nerve fiber. The swelling taste buds contrasted strikingly with the atrophied foliate papillae in the whole STZ rats group. 2. Vacuole formation and pyknosis were seen in the taste buds in 3-month STZ rat group, and 6-month STZ rat group. Increased lipid droplets and a lot of filament bundles are seen in 12-month STZ rat group. 3. A great number of autophagic vacuoles were recognized morphologically as membranous cytoplasmic body (MCB) and zebra body. 4. Swelling mitochondria, rough ER, Golgi apparatus were observed as change of organelle. 5. Intragemmal fibers were enlarged and myelin-like body appeared in subsurface cisternae (ssc) in the Type II cell. Plasma membrane of the nerve ending degenerated in the afferent synapse in the type III cell. On the contrary, afferent synaptic contacts were observed in 12-month STZ rat group as well. 6. Dense substance in the taste pore decreased remarkably in 3-month STZ. It was suggested environment of taste pore changed in the early stage. With the foliate papillae atrophying, taste pore was apt to show stricture. There were also many imperfolate taste pore in 12-month STZ rat. 7. Diabetes showed strong infectiosity. Many taste pores infected with bacteria were observed. On account of these changes in taste buds and nerve element in STZ rats, functional disorder of taste buds were suggested in diabetes mellitus.

Structure of taste buds in foliate papillae of the rhesus monkey, Macaca mulatta.

Taste buds in foliate papillae of the rhesus monkey were examined by electron microscopy. Three distinct cell types were identified. Type I cells were narrow elongated cells containing an oval nucleus, bundles of intermediate filaments, several Golgi bodies, and characteristic apical membrane-bounded dense granules. These cells exhibited morphological variations: some had a moderately dense cytoplasm, perinuclear free ribosomes, and flattened sacs of rough endoplasmic reticulum; others had a more lucent cytoplasm, dilated irregular rough endoplasmic reticulum, lysosome-like dense bodies, and lipid droplets. Type II cells typically contained a spherical, pale nucleus, a prominent nucleolus, supranuclear and infranuclear Golgi bodies, mitochondria with tubular cristae, and one or two centrioles. This cell type, too, showed some variation in the relative amounts of ribosomes and smooth endoplasmic reticulum, which varied inversely with each other. Type III cells were characterized by a clear apical cytoplasm essentially devoid of ribosomes and containing microtubules. In a few type III cells, the peri- and infranuclear regions contained many ribosomes and some rough endoplasmic reticulum. In most Type III cells, there were large numbers of dense and clear vesicles in the peri- and infranuclear regions; some of the vesicles were grouped in synapse-like arrangements with adjacent nerves. The morphological variations exhibited by all three cell types could be accounted for by age differences in each of the cells. This would be consistent with the notion that cell renewal occurs in each of the three cell populations.