Observations regarding the structure of the parotid and mandibular glands in rabbit

Our study aims to investigate the histological structure of two major salivary glands in adult rabbit. We used 5 adult rabbits, 3 males and 2 females, from a private breeder in Cluj. We harvested the salivary glands, fixed them in 10% buffered formalin, dehydrated in ethanol (increasing concentration), clarified in n-butanol and embedded in paraffin. The sections (5 µm thickness) were stained with Goldner’s trichrome method and examined with an Olympus BX41 light microscope. Histologically, parotid gland in rabbit contains only one type of acini, which presents morphological characteristics of serous acini. In mandibular gland, the acini are all the same, similar to the ones in parotid gland. Concerning the general aspect and dimension they are much larger and polymorphic

Assessing the intralobular ducts in mouse mandibular gland

In order to quantify the types of intralobular ducts, we used five adult male mice, sacrificed by cervical dislocation, after exposure to anesthetic. After euthanasing the animals, the mandibular glands were histologically processed. We sectioned the tissue at 5 µm thickness and stained the slides using Goldner’s trichrome staining procedure. We captured images on four different microscopic fields for each animal, subsequently counting each type of intralobulary duct. The granular ducts were the most numerous, followed by the intermediary ones and striated ducts with the lowest number

Intraspecific Differences Regarding Granular Polymorphism in Granular Ducts’ Cells in Rats’ Mandibular Gland

Mandibular gland ducts’ system in rodents consist of intralobular ducts (intercalated, granular, striated) and interlobular one (main excretory duct). Granular ducts are located between intercalated and striated ducts, being present only in mandibular gland of the mouse, rat, hamster and gerbil. The biological material used for this study was represented by two strains from the same species, three Wistar rats and three Brown Norway rats. After the animals were euthanized, the mandibular glands were harvested and then processed for histological investigations. The tissue fragments were sectioned at 5μm thickness and then stained the sections using Tricrom-Goldners method. Our results emphasize that the granular ducts are well developed; regarding the shape, they are convoluted in both Wistar and Brown Norway rats, without any significant differences between the two strains. In Wistar rat, the granules in granular ducts cells are small to medium in size, with discrete polymorphism. In Brown Norway rat, the cytoplasm is loaded with granules as in Wistar rat, but these are several times larger and more polymorphic

Holocrine secretory mechanism in granular ducts in Brown Norway rat. Histological study

Mandibular glands in rodents contain a particular type of ducts, namely granular ducts. The cells lining these ducts present granules in their cytoplasm and secrete different substances. Our study aimed to assess these granules and the secretory mechanisms of these cells. The biological material was represented by 5 adult males Brown Wistar rats. We harvested the mandibular glands and processed them for histological examination. The slides showed that the cells lining the granular ducts present granules of different sizes with a spherical shape. They can occupy up to half of the cell cytoplasm and sometimes even more, forming large aggregates. The secretion of these large aggregates takes place through a holocrine secretory mechanism. The cells presenting this type of mechanism can be easily identified on the slides because they show discontinuity of the apical pole and a tendency of dispersion of the cellular contents. The other two types of secretory mechanisms are also present. In other words, the cells lining the granular ducts from Brown Norway rats mandibular glands, present merocrine, apocrine and holocrine secretory mechanisms. This is the first evidence of the holocrine mechanism cells from granular ducts in mandibular gland in this species

Comparative stereological study of granular and striated ducts in mandibular glands in Wistar and Brown Norway rats

Mandibular glands in adult rats contain granular ducts, derived from the striated ones, which enrich the saliva with different components. The aim of our study was to conduct a comparative stereological study of the striated and granular ducts in two rat strains (albino Wistar and Brown Norway). With this purpose in view, we harvested salivary glands from 5 animals from each strain in part and histologically processed them. We analyzed fields with the total surface of 1699510 μm2 with the aid of AmScope software and the statistical analysis was performed with GraphPad Prism 6.01 program. The results showed that in both species, the number of sections through the granular ducts is higher than the one of striated ducts and the total surface occupied by the granular ducts is higher than the one occupied by the striated ones. The statistical analysis revealed the fact that there are no significant differences between the number of striated or granular ducts from one species to another, nor between the surface occupied by each type of duct (striated or granular) on the sections taken into study in the two rat strains. Thus, the mandibular gland in Wistar and Brown Norway rat resemble one another regarding the surface occupied by the striated and granular ducts and also the number of the two types of ducts on the section taken into study