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At least 19 recordsLinked to original sources
PubMed1991

Further purification and characterization of newly synthesized anionic glycoconjugates secreted by cultured UMR-106 cells: evidence that the major anionic glycoconjugate secreted by these cells is similar to bone sialoprotein II.

Following incubation of UMR-106 cells for 48 h in the presence of [3H]glucosamine and [35S]sulfate, the newly synthesized anionic glycoconjugates were isolated from the culture medium by cetylpyridinium chloride/ethanol precipitation and further separated by DEAE-Sephacel chromatography into two radiolabelled fractions, a major component, UM I, and a minor component, UM II. UM I appeared to be homogeneous as shown by Sepharose CL-4B chromatography under dissociative conditions, and SDS-polyacrylamide gel electrophoresis. It showed a molecular mass of approximately 93 kDa on 4-15% gels. UM I was partially degraded by brief treatment with trypsin, releasing a small, terminal peptide that contained 47.6% of 35S but no 3H. Treatment of UM I with neuraminidase and 0.1 N H2SO4 (1 h at 80 degrees C), respectively, released 27% 3H and 38.4% 3H plus 41% 35S, suggesting the presence of a significant number of sialic acid residues, as shown by Sephadex G-50 chromatography of the digests. Amino acid analysis showed that the UM I glycoconjugate was rich in acidic amino acids (12.6% aspartic acid and 21.2% glutamic acid residues) and its N-terminal sequence was Phe-Ser-Met-Lys-Asn-Phe-, which is identical to the published N-terminal amino acid sequence of rat bone sialoprotein II. Keratanase treatment of UM I released 26% of the incorporated radioactivity, suggesting the presence of keratan sulfate chains. UM II contained a chondroitinase ABC-sensitive proteoglycan.

Amino Acid Sequence↗
PubMed1992

Glycoconjugates of opioid peptides. Synthesis and biological activity of [Leu5]enkephalin related glycoconjugates with amide type of linkage.

Three N-glycoconjugates of the general formula H-Tyr-Gly-Gly-Phe-Leu-NH-R (R = carbohydrate residue) were synthesized in order to determine the influence of some carbohydrate molecules (6-amino-6-deoxy-D-glucopyranose, 2-amino-2-deoxy-D-glucopyranose, beta-D-glucopyranosylamine) on the biological activity, conformation, and stability of the opioid pentapeptide [Leu5]enkephalin. For the preparation of this compound different methods of peptide synthesis (active ester and mixed anhydride) were investigated. In comparison with [Leu5]enkephalin, all three N-glycoconjugates showed higher potency in the guinea pig ileum assay and lower potency in the mouse vas deferens assay, indicating a decrease in delta opioid receptor selectivity.

Amino Acid Sequence↗
PubMed1991

Characterization of glycoconjugates released in vitro by human ovarian carcinoma cells isolated from effusions.

Ovarian carcinoma cell clusters were isolated from patient effusions. The glycoconjugates released to culture medium in vitro were characterized by electrophoretic, immunoassay and gel filtration procedures. Metabolically radiolabelled glycoconjugates were heterodisperse with respect to molecular weight and this heterodispersity was independent of incubation time in vitro. This heterodispersity was also characteristic of mixed Mullerian tumor cells of endometrial origin whereas mesothelial cells released a discrete glycoconjugate of MW 65-70 kDa. Multiple Coomassie blue-stained polypeptides were released by the carcinoma cells. These polypeptides were not adsorbed serum components as assessed by immunodiffusion analyses. Periodic acid-Schiff-reactive macromolecules appeared only at the top of electrophoresis gels. The high molecular weight glycoconjugates synthesized by ovarian carcinoma cells precipitated with an effusion globulin fraction at low ionic strength, but the low molecular weight components (40-70 kDa) were soluble. Immunoprecipitation with anti-Ig failed to precipitate carcinoma glycoconjugates. Antisera raised against the released carcinoma macromolecules precipitated carcinoma glycoconjugates and normal ovarian polypeptides. Antisera raised against normal ovarian macromolecules precipitated ovarian polypeptides but reacted only slightly with carcinoma glycoconjugates. Immunodiffusion analyses showed the presence of alpha 1-acid glycoprotein and carcinoembryonic antigen (CEA)-like components in the carcinoma glycoconjugates. The presence of CEA-like glycoconjugates was confirmed by immunoprecipitation. The antigens and antisera for different histologic types of ovarian carcinoma were cross-reactive. The presence of beta 2-microglobulin suggested that some of the glycoconjugates were shed from the cell surface.

Ascitic Fluid↗
PubMed1989

Platelet-activating factor increases platelet-dependent glycoconjugate secretion from tracheal submucosal gland.

Using isolated glands from feline trachea, we examined the effect of platelet-activating factor (PAF) on radiolabeled glycoconjugate release and glandular contraction by measuring induced tension in the absence or presence of platelets. PAF alone did not produce any significant glandular contraction nor any significant change in glycoconjugate release from isolated glands. In the presence of purified platelets containing no plasma, PAF (10(-8) to 10(-5) M) produced significant glycoconjugate secretion in a dose-dependent fashion, but it produced no significant glandular contraction. PAF-evoked glycoconjugate secretion was time dependent, reaching a peak response of 277% of control 15-30 min after the exposure of isolated glands to 10(-5) M PAF in the presence of platelets and returning to 135% of controls at 2 h. Platelets alone did not produce any significant stimulation in glycoconjugate release. CV-3988, a known PAF antagonist, inhibited the secretory response to PAF. Methysergide, a known antagonist to receptors for 5-hydroxytryptamine, did not alter PAF-evoked glycoconjugate secretion. Both indomethacin and SQ 29,548, a thromboxane receptor antagonist, abolished the PAF-evoked glycoconjugate secretion from isolated submucosal glands. Epithiomethanothromboxane A2, a stable thromboxane A2 analogue, produced a significant increase in glycoconjugate secretion in a dose-dependent fashion. These findings indicate that PAF increases glycoconjugate release in the presence of platelets and that the increase is dependent on some aspect of platelet function, namely thromboxane generation.

Animals↗
PubMed1989

Synthesis and release of glycoconjugates bearing N-linked oligosaccharides by ovarian carcinoma cells isolated from effusions.

Ovarian carcinoma cell clusters were isolated from patient effusions. The cell isolates were incubated in vitro with radioactive glycoconjugate precursors. Radiolabelled glycoconjugates released to culture media were analyzed for molecular mass heterogeneity and lectin binding activity. From 10 to 50% of the released glycoconjugates were present as a heterogeneous array of glycoconjugates of molecular mass greater than 250 kilodaltons. The remaining glycoconjugates were dispersed in a molecular mass range extending down to approximately 15 kilodaltons. Concanavalin A-Sepharose affinity chromatography revealed the presence of N-linked oligosaccharides. Interaction of glycoconjugates with lentil and pea lectins indicated the presence of L-fucose residues linked to asparagine-bound N-acetylglucosamine. Precipitation of glycoconjugates with ricinus communis agglutinin I showed the presence of nonreducing terminal N-acetyllactosamine residues. Collectively, the data indicate that ovarian carcinoma cells release to culture medium fucosylated glycoconjugates bearing complex-type oligosaccharides. The synthesis and release of these glycoconjugates showed no significant differences among different histologic types of ovarian carcinoma; however, modulation as a function of tumor progression may occur.

Cell Separation↗
PubMed1992

Ibuprofen augments bradykinin-induced glycoconjugate secretion by human nasal mucosa in vivo.

Bradykinin (BK) stimulates vascular permeability and glycoconjugate secretion in human nasal mucosa. Since some of the effects of BK may be mediated by autocrine generation of arachidonic acid metabolites, the influence of ibuprofen, a cyclooxygenase inhibitor, on BK-induced nasal secretion was studied. Six normal male subjects had nasal provocations with 0, 10, 100, and 1000 nmol of BK before and after treatment with 400 mg of ibuprofen. Secretions were collected by nasal lavage. Total protein (marker of protein secretion), glycoconjugate (mucous cell marker), lysozyme (serous cell marker), and albumin (marker of vascular permeability) were measured. Basal glycoconjugate secretion was higher after ibuprofen (219 +/- 32 micrograms/ml) than before (81 +/- 56 micrograms/ml; p less than 0.05 by analysis of variance). BK stimulated significant, dose-dependent albumin, total protein, and glycoconjugate secretion. Lysozyme secretion was not stimulated. BK (1000 nmol) significantly increased total protein secretion, tenfold to twentyfold, and albumin secretion by 40-fold to 60-fold. Ibuprofen did not alter BK-induced total protein or albumin secretion. Glycoconjugate secretion after ibuprofen treatment was significantly higher than normal at 10 nmol (p less than 0.05), 100 nmol (p less than 0.02), and 1000 nmol of BK (519 micrograms/ml +/- 74 versus 213 +/- 15 micrograms/ml; p less than 0.05). Therefore, BK induces vascular permeability and exocytosis from glycoconjugate-containing cells but does not stimulate serous cells. Ibuprofen increases baseline secretion of glycoconjugate and enhances BK-induced glycoconjugate secretion. Ibuprofen does not alter BK-induced vascular permeability.

Adult↗
PubMed1989

Synthesis and release of glycoconjugates in vitro by human ovarian carcinoma cells isolated from effusions.

Human ovarian carcinoma cells were isolated as multicellular aggregates from patient effusions. Freshly isolated cells were incubated with radioactive glycoconjugate precursors and the glycoconjugates released to culture medium were analyzed. The glycoconjugates appeared to contain both O- and N-linked oligosaccharides. Both fucosylation and sialylation of glycoconjugates occurred. The results of SDS-PAGE analysis showed the presence of a very heterogeneous array of glycoconjugates with no discrete components resolved. The results of glycoconjugate analyses were independent of carcinoma histology, differentiation, progression, and patient chemotherapy. In contrast, mesothelial cells synthesized a major glycoconjugate of molecular mass 65 KDa. The heterogeneous array of carcinoma-derived glycoconjugates may be transformation-related and may have utility in tumor diagnosis and prognosis.

Carbon Radioisotopes↗
PubMed1991

Changes of glycoconjugate contents of the zona pellucida during oocyte growth and development in the golden hamster: a quantitative cytochemical study.

We demonstrated here with the high resolution lectin-gold approach and quantitative analysis, changes of glycoconjugates in the hamster zona pellucida (ZP) during oocyte growth and development in the ovary and the oviduct. Glycoconjugates which contain N-acetyl-D-galactosamine as terminal sugar residues are absent in the ovary but are secreted by secretory cells in the oviduct and are added to the ZP of superovulated oocytes during oviductal transit. Glycoconjugates which carry sialic acid as terminal sugar residues appear to be acquired mainly from the ovary. The oviduct contributes little of this particular component to the ZP during the transit of oocytes in the oviduct. On the contrary D-galactose and N-acetylglucosamine associated glycoconjugates, added to the ZP in ovarian follicles, are also secreted by non-ciliated oviductal epithelial cells and these secretory products are transferred to the ZP in significant amount during passage of the oocyte through the oviduct. Lectin-gold labeling of the ZP of superovulated oocytes reveals homogeneous distribution of gold particles throughout the zona matrix. Thus, we conclude that the ZP of hamster superovulated oocytes consists of glycoconjugates that may derive from different origins. Deposition of ZP glycocomponents begins in the ovary. Similar and new glycoconjugates, secreted by oviductal non-ciliated secretory cells, are added to the ZP of oocytes during oviductal transit. At this stage the ZP is made up of a homogeneous matrix of glycoconjugates.

Animals↗
PubMed1992

Malaria sporozoites and circumsporozoite proteins bind specifically to sulfated glycoconjugates.

Circumsporozoite (CS) proteins, which densely coat malaria (Plasmodia) sporozoites, contain an amino acid sequence that is homologous to segments in other proteins which bind specifically to sulfated glycoconjugates. The presence of this homology suggests that sporozoites and CS proteins may also bind sulfated glycoconjugates. To test this hypothesis, recombinant P. yoelii CS protein was examined for binding to sulfated glycoconjugate-Sepharoses. CS protein bound avidly to heparin-, fucoidan-, and dextran sulfate-Sepharose, but bound comparatively poorly to chondroitin sulfate A- or C-Sepharose. CS protein also bound with significantly lower affinity to a heparan sulfate biosynthesis-deficient mutant cell line compared with the wild-type line, consistent with the possibility that the protein also binds to sulfated glycoconjugates on the surfaces of cells. This possibility is consistent with the observation that CS protein binding to hepatocytes, cells invaded by sporozoites during the primary stage of malaria infection, was inhibited by fucoidan, pentosan polysulfate, and heparin. The effects of sulfated glycoconjugates on sporozoite infectivity were also determined. P. berghei sporozoites bound specifically to sulfatide (galactosyl[3-sulfate]beta 1-1ceramide), but not to comparable levels of cholesterol-3-sulfate, or several examples of neutral glycosphingolipids, gangliosides, or phospholipids. Sporozoite invasion into hepatocytes was inhibited by fucoidan, heparin, and dextran sulfate, paralleling the observed binding of CS protein to the corresponding Sepharose derivatives. These sulfated glycoconjugates blocked invasion by inhibiting an event occurring within 3 h of combining sporozoites and hepatocytes. Sporozoite infectivity in mice was significantly inhibited by dextran sulfate 500,000 and fucoidan. Taken together, these data indicate that CS proteins bind selectively to certain sulfated glycoconjugates, that sporozoite infectivity can be inhibited by such compounds, and that invasion of host hepatocytes by sporozoites may involve interactions with these types of compounds.

Amino Acid Sequence↗
PubMed1987

Dog tracheal epithelial cells in culture synthesize sulfated macromolecular glycoconjugates and release them from the cell surface upon exposure to extracellular proteinases.

To determine whether glycoconjugates can be released into airways by surface epithelial cells that do not contain secretory granules and, if so, whether extracellular proteinases can affect this release, we studied dog tracheal epithelial cells after 8-10 days in culture. Ultrastructurally, these cells showed an extensive cell surface coat and no secretory granules. Cells were pulse labeled with radioactive sulfate (Na2 35SO4, 50 microCi/ml/24 h) and washed free of the unbound label. Release of sulfated products was then measured at 20-min intervals under basal conditions and again after 20 min of incubation with various extracellular proteinase. We found that these cells synthesized sulfated products and released them spontaneously and continuously into the medium. In addition, trypsin, Pseudomonas aeruginosa elastase, thermolysin, Staphylococcus aureus proteinase, mast cell chymase, plasmin, and kallikrein (each at 10(-7) M except plasmin, at 5 X 10(-6) M) increased the release of sulfated products to 77-667% over baseline release (p less than 0.01, n = 5 dogs for each); preliminary results showed that human neutrophil elastase was also very potent. The sulfated products released by trypsin had an apparent molecular weight of greater than or equal to 10(6) da as determined by gel filtration on Sepharose Cl-4B. Over 50% of these 35S-labeled products were digested to low-molecular-weight products (500-2000 da) upon incubation with endo-beta-galactosidase or with keratanase, suggesting that they are glycoconjugates containing poly(N-acetyllactosamine)-type carbohydrate chains. Decrease in cell staining by lectins specific for poly(N-acetyllactosamine), which accompanied the release of glycoconjugates, indicates that these sulfated glycoconjugates were released by proteinases from the apical cell surface. We conclude that cultured tracheal epithelial cells synthesize and transport sulfated macromolecular glycoconjugates to apical cell surfaces. These glycoconjugates are released from cell surfaces when exposed to extracellular proteinases. We therefore suggest that macromolecular glycoconjugates in airway secretions can originate not only from secretory granules but also from epithelial cell surfaces during airway inflammation.

Animals↗
PubMed1992

Morphology and glycoconjugate histochemistry of the palpebral glands of the adult newt, Notophthalmus viridescens.

The eyelids of the newt were studied in 10 microns serial paraffin and 1-2 microns plastic sections using standard histological stains and special stains for glycoconjugates. The eyelids contain four different glands. Simple acinar serous and simple acinar mucous glands occur in the skin; unicellular mucous glands occur in the conjunctiva; and convoluted tubular seromucous glands are present in connective tissue beneath the conjunctiva. The first two are identical to cutaneous glands found elsewhere on the head and body. The simple acinar serous glands are surrounded by myoepithelial cells and release their secretion, which is composed largely of proteins with minimal glycoconjugate content, by a holocrine mechanism. The secretory product of the simple acinar mucous glands is composed of neutral glycoconjugates with a minor content of acidic glycoconjugates; the mucin exhibits strong PAS and PAPD staining and weak staining by AB and PAPS methods. The unicellular conjunctival mucous glands secrete both neutral and acidic glycoconjugates as shown by positive reactions with PAS, PAPD, PAPS, and AB methods. Convoluted tubular seromucous glands in the ventral eyelid synthesize both proteins and neutral glycoconjugates. The mucous secretions of the conjunctival glands probably provide lubrication and protection for the cornea.

Animals↗
PubMedDate not supplied

Released glycoconjugate of indigenous Leishmania major enhances survival of a foreign L. major in Phlebotomus papatasi.

The effect of Leishmania glycoconjugate in the vector was investigated using Phlebotomus papatasi artificially infected with a Leishmania major strain that this vector does not transmit in nature. Glycoconjugate of the vector-specific strain of L. major was added to the infective meals of some fly groups and the success of infections with or without this substance was compared 4 d later. In the absence of glycoconjugate the parasites survived in 15.6% of the flies, while the addition of 0.5 mg/ml and 2 mg/ml raised the rate of infection to 34.3% and 63.0% respectively. Undigested blood was found in the stomach of 7.8% of the infected flies, whereas following meals with parasites and 2 mg/ml glycoconjugate it was present in 37% of the flies. The results demonstrated that this glycoconjugate increased the viability of the parasites in the unsuitable vector and delayed digestion of the infective meals. In a parallel experiment the glycoconjugate of L. donovani did not affect the survival of the parasites.

Animals↗
PubMed1987

Membrane glycoconjugates as potential mediators of alcohol effects.

1. Membrane glycoconjugates include glycoproteins and glycolipids that have many important functions in a wide variety of tissues, especially brain. 2. Alcohol's ability to fluidize and swell plasma membranes could be expected to alter the orientation and conformation of the embedded glycoconjugates. 3. Both kinds of glycoconjugates can contain terminal moieties of sialic acid, which has been shown to be decreased by single doses of alcohol. Chronic exposure to alcohol may have no effect on sialic acid, except in very young animals. 4. Glycolipids containing sialic acid (gangliosides) are also decreased by acute doses of alcohol, but chronic alcohol has little effect. Thus, gangliosides may have a role in the development and expression of tolerance. 5. Glycoproteins containing sialic acid may also be involved in alcohol action, but there has been less research in this area. 6. Alcohol-induced disruptions in membrane glycoconjugates could affect the important cellular functions that glycoconjugates have, and thus research on alcohol effects on glycoconjugates could lead to important discoveries of diagnostic and therapeutic value for alcohol abuse and alcoholism.

Alcoholic Intoxication↗
PubMed1992

Vagal control of mucus glycoconjugate secretion into the feline trachea.

1. We examined the effects of frequencies and patterns of electrical stimulation of the peripheral cut ends of the vagus nerves on the release of mucus glycoconjugates into feline trachea in vivo. Mucus glycoconjugates, radiolabelled biosynthetically with [35S]sulphate and [3H]glucose, were washed from a tracheal segment in situ, and dialysed before being counted and assayed chemically by the periodic acid-Schiff (PAS) method. 2. Vagal stimulation with regular pulses (10 V, 2 ms duration) at 1, 2.25, 4.5, 9 and 18 Hz produced frequency-dependent increases in the output of mucus glycoconjugates. 3. The muscarinic agonist pilocarpine (0.1-10 microM), given intrasegmentally, produced dose-dependent increases in the output of mucus glycoconjugates. 4. Pretreatment with atropine, phentolamine and propranolol reduced but did not abolish the effects of vagal stimulation. Vagus nerve stimulation still caused frequency-dependent increases in the output of mucus glycoconjugates. 5. High frequency stimulations at 22.5 and 47.5 Hz given intermittently (1 s burst then 4 s rest), whether in the absence or presence of cholinergic and adrenergic blockade, produced similar secretory responses as the same number of pulses delivered in regular trains at 4.5 and 9.5 Hz. This suggests that neither cholinergic nor non-adrenergic, non-cholinergic (NANC) nerve mechanisms in this system are potentiated by high frequency, intermittent burst stimulation. 6. In the absence of atropine, regular vagal stimulation had a greater effect on heart rate than did the same number of pulses delivered in bursts. 7. High molecular weight glycoconjugates from secretions were taken from the void volume of a Sepharose CL-2B gel filtration column and separated further by density-gradient centrifugation. Macromolecular components were observed at two densities, a typical mucin at 1.52 g ml-1, and a high density atypical component at 1.63 g ml-1. In secretions collected during vagal stimulation, either in the absence or presence of cholinergic and adrenergic blockade, the ratio of low density to high density macromolecules was higher than in unstimulated secretions. This can be explained if both cholinergic and NANC nervous vagal mechanisms stimulate the output of typical (density = 1.52 g ml-1) mucins into the feline trachea.

Adrenergic Fibers↗
PubMed1992

Transient cholinergic glycoconjugate secretion from swine tracheal submucosal gland cells.

By inference, muscarinic stimulation of glycoconjugate release from tracheal submucosal gland cells appears to be a transient, nonequilibrium process (J. M. Farley and T. M. Dwyer, Life Sci. 48: 59-67, 1991). To directly characterize the release kinetics of glycoconjugate, we developed an enzyme-linked lectin assay (ELLA) of much improved precision and resolution. To collect secreted products with an improved time resolution, freshly isolated swine tracheal submucosal gland cells were continuously superfused with medium 199 at 37 degrees, buffered with N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) and CO2 or bicarbonate; fractions were collected every 15 s to 2 min. A 30-s pulse of 30 nM acetylcholine (ACh) increased the rate of glycoconjugate release by 10- to 25-fold for 2-3 min. The peak response averaged 14.2 +/- 9.0 ng protein.ml-1.min-1. 4 million cells-1 or 3.6 +/- 2.3 fg.cell-1.min-1 for 30 nM ACh and 16.2 +/- 3.0 ng protein.ml-1.min-1 for 100 nM ACh. There was no significant glycoconjugate release following a 30-s pulse of either 10 nM or 1 microM ACh. A second pulse after 7 min had no measurable effect on glycoconjugate release but a full response was obtained after 30 min. A continuous superfusion begun 1 min following the 30-s pulse resulted in a greater release of glycoconjugate than the pulse alone, but the response was not sustained, falling to twice basal levels within 5 min. We conclude that a brief muscarinic stimulation causes a triggered release of mucus glycoprotein followed by a relative refractory period.

Acetylcholine↗
PubMed1988

Histochemistry of glycoconjugates in the goat nasolabial skin with special reference to eccrine glands.

The histochemistry of glycoconjugates in the nasolabial skin of the goat has been studied by means of a series of selected methods of light microscopy. The epidermis of the nasolabial skin was found to contain neutral and acid glycoconjugates with different saccharide residues. The secretory epithelial cells and secretory substances of the sebaceous glands contained primarily neutral glycoconjugates, whereas those of the apocrine glands involved largely strongly acidic and neutral glycoconjugates. In the epithelial cells and secretory substances of the nasolabial eccrine glands, glycoconjugates involved were characteristically strongly neutral but weakly acidic in nature. From the present results, the histophysiological significance of glycoconjugates in the particular histologic structures of the nasolabial skin has been discussed with special reference to the functions of this particular skin type in the goat.

Animals↗
PubMed1990

Direct inhibitory action of glucocorticoid on glycoconjugate secretion from airway submucosal glands.

The precise mechanism by which glucocorticoids inhibit airway mucus secretion is still unknown. To study directly the effect of glucocorticoid on submucosal gland secretion, we examined the effects of dexamethasone on the precursor uptake, biosynthesis, and release of mucus glycoprotein in isolated feline tracheal submucosal glands. Mucus glycoprotein release from isolated glands was estimated by measuring [3H]glucosamine-labeled trichloroacetic acid (TCA)-precipitable glycoconjugates secreted into the medium. Released glycoconjugate per hour per dry weight of gland tissue was less than 7% of the total intracellular content, where intracellular content is defined as total 3H activity in the dissolved gland tissue. Treatment with 10(-9) to 10(-5) M dexamethasone for 24 to 72 h significantly reduced basal glycoconjugate secretion up to 22% of control (a 78% decrease) in a dose-dependent fashion, whereas the total intracellular 3H content was reduced to 70% of control (a 30% decrease) with no statistically significant differences from controls. The ratio of released glycoconjugates to the total intracellular content decreased significantly to 31% of control (a 69% decrease) after the treatment with 10(-10) to 10(-5) M dexamethasone. Further, ratio of radioactivity of TCA-precipitable glycoconjugates in the dissolved gland tissue to the total intracellular 3H content increased from 40% in nontreated controls to 46% after the treatment with dexamethasone (10(-5) M). Dexamethasone also inhibited the glycoconjugate secretion stimulated by dibutyryl cyclic AMP and alpha- and beta-adrenergic agonists. Simultaneously, the ratio of released to total intracellular content also decreased significantly after dexamethasone treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗