The sphingolipid metabolite sphingosine-1–phosphate (SPP) has been implicated as a second messenger in cell proliferation and survival. However, many of its biological effects are due to binding unidentified receptors on the surface. SPP activated heterotrimeric guanine nucleotide protein (G protein)–coupled orphan receptor EDG-1, originally cloned Endothelial Differentiation Gene – 1 . EDG-1 bound with high affinity (dissociation constant = 8.1 nM) specificity. Overexpression induced...

Human ductal saliva contributes over a thousand unique proteins to whole oral fluids. The mechanism by which most of these are secreted salivary glands remains be determined. present study used mass spectrometry-based, shotgun proteomics approach explore the possibility that subset found in derived from exosomes, membrane-bound vesicles endosomal origin within multivesicular endosomes. Using MudPIT (multidimensional protein identification technology) spectrometry, we catalogued 491 exosome...

After intraarticular injection of TGF-beta 1 or 2, marked swelling and erythema the injected joints were apparent within 12-24 h. On a scale 0 to 4, by day 3, TGF-beta-treated had articular indices (AI) 3.6 +/- 0.5 4.0 0.0 compared with no response for vehicle-injected contralateral joints. Histopathologic evaluation revealed predominantly mononuclear phagocyte infiltrate some neutrophils T lymphocytes, consistent active inflammation. The monocytic pattern leukocyte infiltration at 2-3 d was...

Electron microscope radioautography has been used to study hormone-receptor interaction. At intervals of 3, 10, and 20 min after the injection 125I-insulin, free hormone was separated from bound by whole body perfusion with modified Ringer's solution. The localization hormone, fixed in situ glutaraldehyde, determined. 3 min, 125I-insulin shown be exclusively localized hepatocyte plasmalemma (Bergeron et al., 1977, Proc. Natl. Acad. Sci. U. S. A., 74:5051--5055). In present study,...

In this report, sphingosine-1-phosphate (S1P), a serum-borne bioactive lipid, is shown to activate tight-junction-associated protein Zonula Occludens-1 (ZO-1), which in turn plays critical role regulating endothelial chemotaxis and barrier integrity. After S1P stimulation, ZO-1 was redistributed the lamellipodia cell-cell junctions via S1P1/Gi/Akt/Rac pathway. Similarly, both integrity cell motility were significantly enhanced S1P-treated cells through Gi/Akt/Rac Importantly, S1P-enhanced...

The septate junctions and gap of Hydra were studied utilizing the extracellular tracers lanthanum hydroxide ruthenium red. Analysis junction from four perspectives has shown that each septum consists a single row hexagons sharing common sides 50-60 A. Each hexagon is folded into chair configuration. Two sets projections emanate corners hexagons. One set (A projections) attaches to cell membranes at 80-100-A intervals, while other (V joins some adjacent septa other. generally contain few...

The fine structure of von Ebner's gland was studied in untreated rats and stimulated to secrete by fasting-refeeding or injection pilocarpine. Cytological features were similar those reported for pancreas parotid gland. Abundant granular endoplasmic reticulum filled the basal portion cell, a well-developed Golgi complex located vicinity nucleus, apical cell with dense secretory granules. Dense heterogeneous bodies resembling lysosomes closely associated complex. Coated vesicles seen region...

Breakdown of the nuclear envelope (NE) was analyzed in live starfish oocytes using a size series fluorescently labeled dextrans, membrane dyes, and GFP-tagged proteins pore complex (NPC) lamina. Permeabilization nucleus occurred two sequential phases. In phase I NE became increasingly permeable for molecules up to ∼40 nm diameter, concurrent with loss peripheral components over time course 10 min. The remained intact on ultrastructural level during this time. II completely permeabilized...

The salivary fluid secretory mechanism is thought to require Na⁺/K⁺/2Cl⁻cotransporter-mediated Cl⁻ uptake. To directly test this possibility we studied the <i>in vivo</i> and vitro</i>functioning of acinar cells from parotid glands mice with targeted disruption Na⁺/K⁺/2Cl⁻cotransporter isoform 1 (<i>Nkcc1</i>), gene encoding Na⁺/K⁺/2Cl⁻cotransporter. In wild-type NKCC1 was localized...

Abstract The parenchyma of the submandibular gland in adult male rat is self‐renewing, with most newly formed acinar and granular duct cells believed to differentiate from rapidly proliferating intercalated (ID) compartment. Since ID are phenotypically diverse, based on their different expression perinatal secretory proteins, we systemically injected tritiated thymidine for 24 hours, followed pattern distribution by autoradiography immunocytochemistry defined cellular phenotypes over a...

To investigate potential physiological interactions between the transcellular and paracellular pathways of water transport, we asked whether targeted deletion Aquaporin 5 (AQP5), major transporter in salivary acinar cells, affected transport 4-kDa FITC-labeled dextran (FITC-D), which is transported through but not route. After i.v. injection FITC-D into either AQP5 wild-type or AQP5−/− mice saliva collection for fixed time intervals, show that relative amount half matched AQP5+/+ mice,...

A new cytochemical method is presented for the light and electron microscopic localization of lysosomes in mineralized soft tissues. Inorganic trimetaphosphate used as substrate a lead chelate incubation medium at pH 3.9. Lysosomes several tissues are strongly reactive, reaction product frequently present Golgi saccules GERL. The can be differentiated from acid glycerophosphatase activity, relatively insensitive to fixation demineralization procedures, often complete after short times.

Abstract Parotid acinar cells from ad libitum ‐ fed and starved rats were studied using electron microscopic cytochemical techniques. Lysosomes containing acid phosphatase non‐specific esterase activity present in of both libitum‐fed rats. They included lipofuscin‐like bodies, smaller round or irregularly‐shaped multivesicular coated vesicles. After 16–24 hours starvation, lipid droplets had accumulated the basal cytoplasm, secretory granules showed evidence degeneration. These altered...

Diimidoesters are bifunctional reagents which react with the ε-amino group of lysine, forming intermolecular cross-links minimal alteration native properties proteins. To determine optimal conditions for tissue fixation diimidoesters, a cross-linking assay was developed based on assumption that protein aggregates formed by would be water-insoluble. With this method, proportion insoluble in fresh liver 16%, while diimidoester, dimethylsuberimidate (DMS) (16-20 mg/ml, 0.02 M Ca ++ and 0.15...

The organization of the endoplasmic reticulum (ER) in cortex ofXenopus oocytes was investigated during maturation and activation using a green fluorescent protein chimera, immunofluorescence, electron microscopy. Dense clusters ER developed on vegetal side (the opposite meiotic spindle) maturation. Small appeared transiently at time nuclear envelope breakdown, disappeared first polar body formation, then reappeared as larger mature eggs. appearance large correlated with an increase...

Although aquaporin 5 (AQP5) is the major water channel expressed in alveolar type I cells lung, its actual role lung a matter of considerable speculation. By using immunohistochemical staining, we show that AQP5 expression mouse not restricted to cells, but also detected II and tracheal bronchial epithelium. Aqp5 knockout ( −/− ) mice were used analyze function pulmonary physiology. Compared with +/+ mice, significantly increased concentration-dependent bronchoconstriction intravenously...

The arrest of meiotic prophase in mouse oocytes within antral follicles requires the G protein Gs and an orphan member protein–coupled receptor family, GPR3. To determine whether GPR3 activates Gs, localization Gαs follicle-enclosed from Gpr3+/+ Gpr3−/− mice was compared by using immunofluorescence GαsGFP. decreased ratio oocyte plasma membrane versus cytoplasm also amount oocyte. Both these properties indicate that Gs. follicle cells around are necessary to keep prophase, suggesting they...

In vitro studies implicate a molecular link between inflammatory mononuclear cells and alterations in fibroblast growth function. We have extended these observations an experimental animal model which we document the T cell-dependence of fibrosis that occurs after activation cell-mediated immune system by specific antigen. Chronic granulomatous lesions were induced livers susceptible rats intraperitoneal injection group A streptococcal cell walls (SCW). The development granulomas are...