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Under the light microscope, the epithelium of filiform papillae consists of an anterior and a posterior side. On the anterior side of filiform papillae the epithelium exhi­bited characteristics of soft keratinization, while on the posterior side - there were charac­teristics of hard keratinization. Conical papillae were covered by nonkeratinized epithe­lium. The keratinized layer was observed only on their ends. The filiform and conical pa­pillae were separated by the interpapillary epithelium, which does not keratinize. The epi­thelium of the filiform and conical papillae were composed of three layers, i.e. basal, in­termediate, and superficial layer.
Studies were conducted on 77 tongues, collected from rabbits being at day 15, 18, 20, 22 and 26 of prenatal life and from rabbits at day 1, 15 and 30 and in the 6th month of postnatal life. Tissues for analyses, collected from the lateral surfaces of the body of the tongue of rabbits, were studied under a light microscope (LM) and a scanning electron microscope (SEM). The thickness of the epithelium in successive periods of pre- and postnatal life was analyzed morphometrically. As a result of the conducted studies it was shown that the epithelium covering the lateral surfaces of the tongue changes in the course of pre- and postnatal development from an epithelium consisting from 1-2 layers of cells into a nonkeratinized stratified squamous epithelium. The thickness of the epithelium increases in successive analyzed periods of life in rabbits. A rapid growth rate was found for the epithelium in the period from day 26 p.c. The lamina propria mucosae is observed in histological slides starting from day 22 p.c. In the same period the presence of elastic fibers was shown. Glycogen was found in the cytoplasm of the epithelial and mesenchymal cells from day 15 to 20 p.c.
The first signs of formation of the posterior serous lingual glands (von Ebner's glands) were observed at day 22 of prenatal development of the rabbit. The development of glands was initiated by the appearance of epithelial bands, growing into the connective tissue. At day 26 p.c. the epithelial bands were longer. At day 1 of postnatal life the secre­tory parts of glands were formed together with excretory parts. Carbohydrates were found in the lumen of the excretory parts. At day 15 p.p. it was shown that the excretory parts opened at the bottom of furrows of foliate and circumvallate papillae. In the successive periods of life in the rabbit were observed linear arrangement for excretory parts opening at the bottom of furrows of foliate papillae. Excretory parts which opened at the bottom of circumvallate papillae formed a circular system.
Rudiments of fungiform papillae were observed at day 18 of prenatal development. They were arranged only on the dorsal surface of the apex of the tongue and its margins. The fungiform papillae looked like a hemispherical, dome-shaped eminences. From day 22 of prenatal development, scanning electron microscope showed also that rudiments of fungiform papillae appeared on the body of the tongue at the front of forming torus linguae, and on its both sides. No rudiments of filiform papillae were observed at day 22 of prenatal development. However, after removal the epithelium, the connective tissue cores of rudiments of fungiform and filiform papillae were visible. Scanning electron microscopy showed on the surface of the tongue numerous filiform papillae at day 26 of prenatal development. They were arranged on the entire dorsal surface of the apex and body of the tongue, and on its margins. During morphogenesis two types of filiform papillae were noticed. One type of filiform papillae was similar to separated cones, another had 3–4 processes more. The similar changes was with the shape of connective tissue core. The fungiform papillae were located among filiform papillae. Scanning electron microscope showed three types connective tissue cores of developing fungiform papillae. One type was mace-shaped, another one was bowl-shaped and yet barred-shaped. At day 30 of postnatal development on the surface of the connective tissue cores of fungiform papillae, from its top towards its base there were parallel and longitudinal folds.
A total of 129 tongues were analyzed, which were collected post mortem from rabbits (Oryctolagus cuniculus f. domestica), aged from day 15 of prenatal development (p.c.) to the 6th month of postnatal life (p.p.). The tongue was formed on the basis of its primordia starting as early as day 15 p.c. At that time the first primordia of lingual papil­lae were observed, which were primordia of circumvallate papillae. At day 18 p.c. the presence of primordia of fungiform papillae was shown, while at day 22 p.c. primordia of foliate and filiform papillae were found. On the dorsal surface of the tongue during the development the torus and median sulcus of the tongue were formed. The median sulcus ended in front of the torus of the tongue. The tongue in the rabbit increased in length from day 22 p.c. to the 6th month p.p. from 9 mm to 65 mm. During that time the weight of the tongue increased from 0.05 g to 9.59 g. The development of the final form of the tongue is a long-term process and occurs both during the prenatal and postnatal life. First primordia of gustatory papillae appear and only later primordia of mechanical papillae are formed.
W pracy określono występowanie Prunus ×eminens ‘Umbraculifera’ na terenie 10 dzielnic Krakowa. Odnaleziono 807 drzew. Najwięcej okazów rośnie w dzielnicy Stare Miasto, najliczniejsze stanowiska znajdują się przy ulicach Cystersów i Pędzichów. Najokazalszym jest drzewo przy ul. Mazowieckiej o obwodzie pnia 185 cm, średnicy korony 9,2 m i wysokości 7,4 m. Wyniki przeprowadzonych obserwacji potwierdzają przydatność tej rośliny do sadzenia w małych, zurbanizowanych przestrzeniach.
Examinations were conducted on four tongues of adult rabbits (Oryctolagus cuniculus). On the basis of observations in a scanning electron microscope (SEM) it was found that fungiform papillae in the rabbit are located on the dorsal surface of the apex and body of the tongue, in the front of the torus of the tongue and on the margins of the tongue. Moreover, fungiform papillae are located laterally in relation to the torus of the tongue and are arranged linearly. Fungiform papillae are distributed among filiform papillae and are separated from them by the interpapillary epithelium. The connective tissue core of fungiform papillae is formed from the body, narrow at the base and wider at the apex and 10-17 crest-like folds arranged around them. On the dorsal surface of the connective tissue core of fungiform papillae there are impressions of taste buds and occasionally traces of lymphatic nodules.
On the root of the tongue in the rabbit there are two symmetrically located vallate papillae, covered by nonkeratinized stratified squamous epithelium. The epithelium is characterized by variable thicknesses, forming epithelial streaks of different length and irregular shape. Taste buds are found both in the epithelium covering the papillae and in the epithelium of the outer walls of the papillae from the side of the furrows. The outer wall of the vallate papillae is gradually transformed with no visible boundary into the surface of the root of the tongue devoid of papillae. The surface of the vallate papillae is uneven. The connective tissue core of the papillae is formed by numerous, irregularly shaped connective tissue papillae, between which epithelial streaks are arranged. Around the connective tissue core of the papillae there is a circular connective tissue fold, with a furrow located on its circumference and the core of the outer wall of the vallate papillae. Numerous excretory ducts of the posterior serous lingual glands (Ebner's glands) open on the fundus of the circular furrow of each vallate papilla. Sometimes excretory ducts of these glands open directly onto the surface of a vallate papilla and then in their vicinity taste buds are found. The results of this study show the structure of vallate papillae on the tongue of adult rabbits, at the same time indicating differences in their structure in comparison to the vallate papillae of other animal species.
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