role of smooth-ended ameloblasts in enamel protein degradation in the rat incisor pigmentation

Rats were perfused with glutaraldehyde. The lower incisors were dissected free. Mid-sagittal slice was cut through the entire incisor, deimneralized. The pigmentation zone was isolated and further sliced into cross sections. These sections were incubated for CMPase. CMPase reaction product were associated with the lateral cell memberane of subclass II and Subclass III. This localization confirm the role of extracellular space of SM as a route of enamel proteins during maturation

Lysosomal system of Von Ebner's salivary gland in the rat

We have examined the morphology and distribution of lysosomes in Von Ebner's salivary gland utilizing TMPase as a marker. TMPase reactivity was detected basally, laterally and in the center of the cells. They include AV, Rb, MVBs and dense bodies. TL was detected for the first time in between the secretory granules and in the lateral parts of exocrine acinar cells. They were parallel to RER. In addition direct continuity between TL and MVBs and dense bodies was observed. The new locations and relations of TL support their role in pinocytotic processes and cellular regularity processes

Light and electron microscopic observation on rat molar periodontal ligament after intraperitoneal injection of vinblastine

The effect of intraperitoneal injection of Vinblastine sulfate on rat periodontal ligament was studied. Cells still synthetize collagen after 2 hours of the injection with evidence of loss of extracellular collagen fibers orientation. Tubular lysosome could not be detected after 2 hours with formation of lysosomal clusters in the cell center. After 4 hours of administration, evidences of cell degeneration were observed. The present study has shown that Vinblastine produces effect on fibroblasts as early as two hours after injection

Histochemical classification of human minor labial salivary glands according to their glycoprotein content

There is debate about the nature of the secretory cells in human labial salivary glands. Histologically, two types of acinar cells were observed. The predominant mucous acini, few basophilic serous acinar cells were detected. Histochemical differentiation of these cells according to their neutral and acidic mucopolysaccharides content using PAS, AB pH 1 and AB pH 2.5 stain revealed the presence of three types of acinar cells, i.e. cells rich in both neutral and acidic mucopolysaccharides, cells rich in either neutral or acidic mucopolysaccharides and cells contain neither neutral nor acidic mucopolysaccharides. The first type constitutes the major component of the gland

Trimetaphosphatase activity in rat incisor odontoblasts during early dentinogenesis

The ultrastructural localization of trimetaphosphatase activity has been investigated in early stages of dentinogenesis in the rat incisor. Extracellular reactive structures were present in-between the odontoblasts during early secretion and absent later on. Tubular lysosomes were observed for the first time in odontoblasts and seemed to be involved with other elements of the lysosomal system in endocytosis of extracellular substances