Bianca Matosz

Microscopic Structure of the Epithelium Lining the Epiglottis in Wistar Rats

The aim of this study was to investigate the type of the epithelium present on the epiglottis surface, through histological examination. The epithelium lining the pharyngeal side of epiglottis is keratinized stratified squamous. The thickness of the keratin layer is different from one subject to another. Usually the keratin layer extends to the apex of the epiglottis, but in some of the animals taken into study, the keratin layer extends to the apical third of the laryngeal side of epiglottis. The epithelium lining the laryngeal side is different. In most of the epiglottises examined, the surface is lined by non-keratinized stratified squamous epithelium in the apical third. The rest of the laryngeal side of the epiglottis is lined by respiratory epithelium type. In one subject, the entire laryngeal surface is lined by a non-keratinized stratified squamous epithelium. Our study highlights that the pharyngeal side of epiglottis is lined by a keratinized stratified squamous epithelium, whereas on the laryngeal side, the epithelium in the apical third is non-keratinized stratified squamous and at the rest of the surface the epithelium is pseudostratified.

The Structure of Urethral Epithelium in Merinos Lambs

The aim of this study was to investigate by histological techniques the structure of urethral epithelium in lambs. In this study, we harvested several fragments (prostatic, membranous and cavernous) from urethra from 5 merino’s lambs of 3 months old. The first anatomical segment, the prostatic urethra, is lined by a urinary epithelium. The intermediary layer of this epithelium is formed of 5-6 rows of oval cells. The second segment of urethra has the same type of epithelium but the intermediary layer is formed of 6-7 rows of oval cells. In the last anatomical segment, the penile urethra, the epithelium is the same, but the intermediary layer has 3-4 rows of oval cells. In lambs, the urethra is lined by urinary epithelium. The urethral epithelium does not have the same thickness in all segments. The thinner epithelium it is in the cavernous urethra, the ticker is the membranous urethra.

MICROSCOPICAL ASPECTS CONCERNING THE PRESENCE AND DISTRIBUTION OF MITOCHONDRIA IN INTRALOBULAR AND INTERLOBULAR DUCTS FROM RAT PAROTID GLAND

Saliva secreted by acini from parotid gland is concentrated in the excretory ducts. This study aims to highlight certain microscopical aspects concerning the presence, density and disposition of mitochondria in intralobular and interlobular ducts from parotid parenchyma in rats. In the intralobular ducts’ segment lined by cuboidal cells, mitochondria are present throughout the whole cytoplasm, without a regular arrangement. In the area where cells are columnar, mitochondria become more numerous and most of them are disposed in the basal half and have a regular disposition (perpendicular to the basal pole). In the interlobular ducts, mitochondria are somehow less, but their disposition is similar to the one in the previous segment. In intralobular ducts with a thin wall, mitochondria have an irregular disposition and are present throughout the whole cytoplasm, while in striated and interlobular ducts, they have a regular disposition, perpendicularly on the basal pole of the cell and most of them are concentrated in the basal half of the cell.

STRUCTURAL PARTICULARITIES OF THE EPITHELIUM LINING THE LAMB EPIGLOTTIS

Epiglottis presents a central axis covered by mucosa. The aim of this study was highlighting the type of epithelium lining the lamb epiglottis. Thus, we histologically processed the epiglottis from 3 lambs. The epithelium lining the whole epiglottis surface is non-keratinized stratified squamous, with different thickness from one side to the other. Hence, on the pharyngeal side the epithelium is twice as thick as the one found on the laryngeal side.