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PubMed1999

Effect of Polyvinyl Pyrrolidone on the Thermal Phase Transition of 1,2 Dipalmitoyl-sn-glycero-3-phosphocholine Bilayer.

The purpose of this study was to investigate the interaction of polyvinyl pyrrolidone (PVP) with phospholipid bilayers in an effort to add a new dimension to our understanding of polymer interaction with lipids. For the preparation of lipid-polymer dispersions, measured amounts of DPPC (1,2 dipalmitoyl-sn-glycero-3-phosphocholine) and PVP were mixed in chloroform. After complete elimination of organic solvent, the dry mixtures were hydrated at 50-55 degrees C. Interactions between DPPC and PVP were assessed by differential scanning calorimetry (DSC) and photon correlation spectroscopy (PS). Separation of liposomes and micelles was performed by centrifugation. Liquid scintillation counting and a UV spectrophotometer were used for their analysis. PVP added as dry powder or added as aqueous solution to dry lipid or preformed liposomes failed to interact. Only PVP previously dissolved in chloroform interacted with DPPC. The DPPC main phase transition moved to lower temperatures with increasing PVP concentrations. This reduction of the phase transition temperature was accompanied by an increase of the DPPC phase transition enthalpy. Analysis of solubilization indicated that the amount of PVP present in the bilayer is dependent on the PVP bulk concentration. The data suggest interaction of PVP previously dissolved in chloroform with the acyl chains of the phospholipid deep into the bilayer. Copyright 1999 Academic Press.

Journal Article↗

PubMed1994

Intragraft expression of messenger RNA for interleukin-6 and tumor necrosis factor-alpha is a predictor of rat small intestine transplant rejection.

Detection of rejection after small intestine transplantation (SIT) is difficult, relying largely on histopathology. The purpose of this study was to determine if the intragraft expression of messenger RNA (mRNA) for interleukin-2 receptor (IL-2R), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF) correlated with rejection in a unidirectional, heterotopic rat SIT model. Graft samples were obtained on postoperative day (POD) 3, 5, 7, 8, 9, 10, 12, and 14. After staining, formalin-fixed samples were blindly evaluated for rejection. Reverse transcriptase polymerase chain reaction (rtPCR) using primers specific for beta-actin, IL-2R, IL-6, and TNF was performed on liquid nitrogen-frozen samples. Semiquantitation was accomplished using radionuclide incorporation and beta-scintillation counting. Intestinal histopathology in all isografts (ISO) and POD 3 allografts (ALLO) was normal. Rejection progressed in ALLO from mild on POD 5 to severe by POD 8. rtPCR analysis revealed constitutive expression of IL-2R mRNA in both ISO and ALLO. TNF and IL-6 demonstrated significant increases in mRNA expression in ALLO compared to ISO beginning on POD 5. In summary, intragraft expression of IL-2R mRNA demonstrated late up-regulation in ALLO which did not correlate with rejection. TNF and IL-6 mRNA expression predicted rat SIT rejection. rtPCR analysis of TNF and IL-6 may serve as a useful diagnostic adjunct for rat SIT rejection.

Animals↗

PubMed1996

A Filter-Based, 96-Well Microtiter Plate Calcineurin Phosphatase Assay

A rapid, sensitive, and specific filter-based assay for calcineurin phosphatase that utilizes a 96-well microtiter plate format throughout is described. In this assay, either purified calcineurin phosphatase or a crude cellular extract containing calcineurin phosphatase is incubated with a 33P-labeled phosphopeptide substrate in a 96-well microtiter plate. Subsequent to quenching the dephosphorylation reaction, the incubation mixture is transferred to a 96-well Immobilon-P microtiter filtration plate affixed to a vacuum manifold. The phosphorylated peptide remains bound to the hydrophobic filter. The filtrate, containing the released 33P-labeled phosphate, is collected in a 96-well microtiter plate and is measured by liquid scintillation counting.

Journal Article↗

PubMed1996

Lactate enhancement of sialylation of gonococcal lipopolysaccharide and of induction of serum resistance by CMP-NANA is not due to direct activation of the sialyltransferase: metabolic events are involved.

Lactate enhances lipopolysaccharide (LPS) sialylation and induction of serum resistance in gonococci by CMP-NANA. To investigate whether the enhancement is due to a direct effect on the sialyltransferase, an improved extraction of the enzyme and a reliable quantitative assay were devised. Gonococci (strain F62) were disrupted in a French pressure cell and the bacterial membranes were extracted for 1 h at 37 degrees C with a detergent, NONIDET (1% v/v). The assay involved sialylation of LPS by CMP-14CNANA and scintillation counting of the labelled LPS after fixing it on filter paper strips by trichloracetic acid (TCA) and washing away unincorporated CMP-14CNANA. It was rapid, reproducible and, although the enzyme preparations contained endogenous LPS, was dependent upon added LPS for maximum activity. At 37 degrees C the rate was constant for up to 5 min and proportional to the concentration of extract in the assay. A wide range of concentrations of lithium-L-lactate did not enhance the activity of the extracted sialyltransferase. At concentrations above 22 microM, it was inhibitory. Pre-incubation of gonococci with lactate enhanced subsequent LPS sialylation and induction of serum resistance by CMP-NANA. Hence, the process whereby lactate enhances the effect of CMP-NANA is separate from the action of CMP-NANA itself. Both processes were inhibited by a sublethal concentration of chloramphenicol, indicating that metabolic events are required. Evidently, the enhancement process does not involve a direct activation of the sialytransferase.

Blood Bactericidal Activity↗

PubMed1995

Progressive application of autoradiography in pharmacokinetic and metabolic studies for the development of new drugs.

Autoradiographic data of distinctive tissue distributions of 14C atoms obtained by labeling at two different positions of a new drug suggest the metabolic fates of each labeled compound in experimental animals. A more accurate determination of blood-brain barrier (BBB) damage in several regions was indicated by semimicroautoradioluminography, based on no passage of dopamine through the BBB. Autoradioluminography (ARLG) was useful for quantitative validation of whole body autoradiography (WBA) with both ordinal X-ray film and other detectors. In frozen specimens, a good correlation was obtained between the relative radioactivity, photostimulated luminescence (PSL), and liquid scintillation counting (LSC) values in each organ or tissue. However, the correlation was disturbed in lung, brain, bone, and adipose tissue after freeze-drying. In order to be listed in the regulatory items, WBA data must be quantitative as well. The paste-mold method presented here can be used to support WBA data. The thin-layer chromatography (TLC)-ARLG technique and its applications are also presented in this article. A blood concentration-time curve of both the parent compound and its unknown metabolites can be estimated with this technique.

Animals↗

PubMed2001

Chemomorphic analysis of malathion in skin layers of the rat: implications for the use of dermatopharmacokinetic tape stripping in exposure assessment to pesticides.

The dermatopharmacokinetic (DPK) method of dermal tape stripping may prove to be a valuable addition to risk assessment protocols for toxic substances as it has been for the assessment of bioequivalence and bioavailability of topical dermatologic drugs. The measurement of drug penetration into stratum corneum (SC) with respect to time is thought to be comparable with drug distribution in underlying tissues. To examine this possibility, the dermal penetration and absorption characteristics of [(14)C]malathion in the Sprague-Dawley rat was examined by three analytical techniques. [(14)C]Malathion was applied in different vehicles for 30-min and 1-h periods of exposure. Penetration into the SC was assessed by tape stripping followed by instant electronic autoradiography (IEA). Also, the (14)C activity retained in three successive 16 microm sections of the skin application site was determined by IEA and malathion was identified by Fourier transform infrared microscopy (FTIR microscopy). Absorbed [(14)C]malathion was measured in selected tissues, organs, and the residual carcass by liquid scintillation counting (LSC). Penetration into the SC followed a linear trend. The capacity of the SC reservoir for malathion amounted to approximately 1% of the dermal dose, while approximately 6% of the dose was absorbed. Results from this study support the view that LSC remains the method of choice to efficiently and reliably quantify absorption of a radiolabeled test substance. IEA offers the ability of the user to visualize the extent and profile of dermal absorption. When IEA is combined with FTIR microscopy, an effectual tool for studying the penetration of chemicals into layers of the skin emerges. The combined use of the three analytical techniques can be used to test the validity of the DPK method in hazard evaluation and exposure assessment of the organophosphorus insecticides.

Animals↗

PubMed1999

Inhibition by lead of production and secretion of transthyretin in the choroid plexus: its relation to thyroxine transport at blood-CSF barrier.

Long-term, low-dose Pb exposure in rats is associated with a significant decrease in transthyretin (TTR) concentrations in the CSF. Since CSF TTR, a primary carrier of thyroxine in brain, is produced and secreted by the choroid plexus, in vitro studies were conducted to test whether Pb exposure interferes with TTR production and/or secretion by the choroid plexus, leading to an impaired thyroxine transport at the blood-CSF barrier. Newly synthesized TTR molecules in the cultured choroidal epithelial cells were pulse-labeled with [35S]methionine. [35S]TTR in the cell lysates and culture media was immunoprecipitated and separated by SDS-PAGE, and quantitated by autoradiography and liquid scintillation counting. Pb treatment did not significantly alter the protein concentrations in the culture, but inhibited the synthesis of total [35S]TTR (cells + media), particularly during the later chase phase. Two-way ANOVA of the chase phase revealed that Pb exposure (30 microM) significantly suppressed the rate of secretion of [35S]TTR compared to the controls (p < 0.05). Accordingly, Pb treatment caused a retention of [35S]TTR by the cells. In a two-chamber transport system with a monolayer of epithelial barrier, Pb exposure (30 microM) reduced the initial release rate constant (kr) of [125I]T4 from the cell monolayer to the culture media and impeded the transepithelial transport of [125I]T4 from the basal to apical side of epithelial cells by 27%. Taken together, these in vitro data suggest that sequestration of Pb in the choroid plexus hinders the production and secretion of TTR by this tissue. Consequently, this may alter the transport of thyroxine across this blood-CSF barrier.

Animals↗

PubMed1998

Kinetics of tissue distribution and elimination of pyrene and 1-hydroxypyrene following intravenous administration of [14C]pyrene in rats.

The tissue distribution and elimination of pyrene and 1-hydroxypyrene (1-OHP) were evaluated in male Sprague-Dawley rats (210-240 g) following an intravenous injection of 50 micromol/kg of [14C]pyrene. Blood and tissues were removed and urine and feces were collected at 1, 2, 4, 8, 16, and 24 h postdosing. [14C]Pyrene equivalents were measured by liquid scintillation counting, and beta-glucuronidase/arylsulfatase-treated blood, tissues, and excreta were analyzed for pyrene and 1-OHP by HPLC/fluorescence. At 1 h, the largest fraction of the dose was found in adipose tissue, essentially as pyrene, and its elimination followed first-order monophasic kinetics with a half-life (t(1/2)) of 4.9 h. In blood, liver, kidney, lung, muscle, and gastrointestinal (GI) tract, kinetics of [14C]pyrene equivalents were biphasic and average t(1/2) values for the terminal elimination phase (8 to 24 h) ranged between 6.2 and 8.7 h. Elimination of pyrene in blood and these tissues except the GI tract followed first-order biphasic kinetics with average t(1/2) values of the terminal phase ranging between 3.6 and 5.4 h. In the GI tract, a monophasic elimination kinetics of pyrene was observed with mean t(1/2) value of 3.1 h. Kinetics of 1-OHP in blood and liver showed a monophasic elimination with mean t(1/2) values of 6.7 and 6.2 h, respectively. Kinetics of 1-OHP in the other tissues were biphasic with average t(1/2) values of the terminal elimination phase ranging between 5.2 and 6.2 h. At 24 h, on average, 81.7% of the dose was recovered in the urine (57.2%), feces (18.3%), and GI tract (6.2%) as [14C]pyrene equivalents with 2.7 and 1.9% of dose excreted as total 1-OHP in urine and feces, respectively. At all time points, 1-OHP in urine represented a constant fraction of total 14C in urine and feces. These results indicate that (i) [14C]pyrene was rapidly distributed, metabolized, and eliminated from the body, and (ii) although 1-OHP represents a small percentage of total pyrene eliminated from the body, it remains a reliable indicator of systemic exposure to, and overall elimination of the 14C associated with, this polycyclic aromatic hydrocarbon.

Animals↗

PubMed2001

Influence of lysine on cimetidine uptake and on excretion of cimetidine by the rat mammary gland.

Cimetidine is actively transported into human and rat milk. However, the transporters involved have not been characterized. It is possible that xenobiotics may be actively transported into milk by an amino acid transport system. The objective of these studies was to determine the influence of lysine on the uptake of cimetidine into rat mammary explants (study 1), and on the excretion of cimetidine into rat milk (study 2). In study 1, excised lactating rat mammary epithelial tissue fragments were exposed to 3H-cimetidine and 14C-lysine in the presence of 10 microM, 1 mM, or 1 M cold lysine, and the uptake of 3H-cimetidine and 14C-lysine were measured by liquid scintillation counting after 5 or 20 minutes of incubation. After 5 minutes of incubation, 1 M lysine inhibited 3H-cimetidine uptake by 47.7% (SD +/- 6.5%), compared with 10 microM lysine (P < 0.05), and 14C-lysine uptake was also inhibited by 54.1% (SD +/- 6.4%) (P < 0.05). Similar results were seen after 20 minutes of incubation. In a randomized crossover study (study 2), 6 lactating female rats were infused to steady state with cimetidine (0.5mg/h) in the presence or absence of lysine (360mg/h). Cimetidine concentrations in serum and milk were determined by high-performance liquid chromatography. Cimetidine systemic clearance (28.6+/-15.0mL/kg/min vs. 38.9+/-3.9 mL/kg/min, mean +/- SD) and milk to serum cimetidine ratio (M/S) (28.0+/-16.1 vs. 28.9+/-6.7), respectively, were not significantly altered by the presence or absence of lysine. Although 1 M lysine inhibited uptake of cimetidine in rat mammary explants, the concentrations of lysine used in this study, which approached toxicity in vivo, produced no significant effects on cimetidine transport into milk or the systemic clearance of cimetidine.

Animals↗

PubMed1979

A simple radioassay for human urinary kallikrein.

We have developed a sensitive, highly selective assay for human urinary kallikrein (HUK) that uses Pro-Phe-Arg-[3H]benzyl-amide as substrate. The substrate was prepared from Pro-Phe-Arg-3-iodo-benzylamide by dehalogenation in 3H2 gas. HUK is measured by its ability to release [3H]benzylamine. The pH optimum is 9.5. Urokinase, plasmin and thrombin do not interfere. The assay can measure as little as 5 ng of HUK in a 15 min incubation at 37 degrees C. Typically, we use 50 microliter of dialyzed urine for HUK assays. Reactions are terminated by adding 0.1 M NaOH, and reaction product is separated from substrate by partitioning with an equal volume of toluene. A sample of the toluene phase is submitted for liquid scintillation counting. As judged by separations obtained on molecular sieve chromatography (Sephacryl), only one urinary enzyme possesses the ability to hydrolyze our substrate. The enzyme MW 45,000, is inhibited by Trasylol but not by soya bean trypsin inhibitor (SBTI). It is reactive with and is inhibited by antibodies prepared against pure HUK.

Acylation↗

PubMed1978

Hepatic clearance and disposition of hydroxyethylrutosides.

Although salts of rutin on i-v admin. undergo insolubilization giving rise to concretions and suppurative inflammation in the liver this was not observed in respect of the vaso-active hydroxyethylrutosides (Pfeifer et al., 1970). I-v admin. of 3',4',7-tri0-(beta-hydroxy[14C]ethyl)-rutoside (tri-HR) and 7-mono0-(beta-hydroxy[14C]ethyl)rutoside (mono-HR) to mice showed rapid biliary excretion (approx. 71% within 24 h). Approx. 2/3 of the dose was subsequently excreted in faeces and ca. 25% in urine over 72 h. Autoradiography and scintilation counting showed short term concentration in the liver over the initial 4 h period but at 72 h less than 0.22% of tri-HR and 0.59% of mono-HR was detectable in hepatic tissue. Carcasses of mice killed at 72 h contained less than 7% of the initial dose which was mainly present in intestinal contents.

Animals↗

PubMed1998

Influence of maturation and ageing on the biotransformation of noradrenaline in the rat.

The present investigation was undertaken to study the influence of maturation and ageing on the disposition of noradrenaline by the aorta, heart (ventricle), liver and kidney of the rat. Slices of these tissues taken from rats aged less than 18 h, 2.5-3 months or 18-24 months were incubated with 0.1 mumol.l-1 3H-amine during 30 min. At the end of this period, the accumulation of the intact amine in the tissue, as well as the 3H-metabolites formed (3,4-dihydroxyphenylethylglycol, 3,4-dihydroxymandelic acid, normetanephrine and O-methylated deaminated metabolites) were determined by scintillation counting. The results obtained show that in the rat: 1) at any age, noradrenaline is preferentially deaminated; 2) while the capacity of the sympathetic nerve terminals in accumulating noradrenaline is rather well developed at birth, the metabolic system for its degradation is still immature; 3) aldehyde dehydrogenase activity or that of its co-factor (or both) of the heart is apparently missing at birth; 4) removal of noradrenaline by the liver and the kidney did not change with ageing, while that by the aorta decreased and that by the heart increased.

Aging↗

PubMed1992

Cloning and characterization of a pathogen-induced chitinase in Brassica napus.

A chitinase cDNA clone from rapeseed (Brassica napus L. ssp. oleifera) was isolated. The cDNA clone, ChB4, represents a previously purified and characterized basic chitinase isozyme. The longest open reading frame in ChB4 encodes a polypeptide of 268 amino acids. This polypeptide consists of a 24 amino acid N-terminal signal peptide, a cysteine-rich domain and a catalytic domain. The primary structure of the mature ChB4 shows a low degree of identity with class I and II chitinases, 43-48% and 35%, respectively. In contrast, ChB4 shows 62% identity to a basic sugar-beet chitinase and 63% identity to an acidic chitinase from bean. The expression of chitinase messenger RNA (mRNA) in response to infection with Phoma lingam (Tode ex. Fr.) Desm. was examined by northern hybridization and scintilation counting. A differential induction was seen between resistant and susceptible cultivars where 3-fold higher chitinase transcript levels were estimated one day after inoculation in resistant as compared to susceptible cultivar. This difference diminished eight days after inoculation. Southern hybridization analysis indicates that the chitinase is encoded by a small family of genes.

Amino Acid Sequence↗

PubMed1991

Primer extension studies on alpha-amylase mRNAs in barley aleurone. I. Characterization and quantification of the transcripts.

Primer extension was used to characterize alpha-amylase mRNAs from aleurone tissue of barley (Hordeum vulgare L. cv. Himalaya) grains. Two synthetic oligonucleotides, specific for the low-pI and high-pI alpha-amylase groups, were used as primers for synthesis of cDNA from total RNA preparations. Between them, these two oligonucleotides appear to account for all major alpha-amylase mRNAs as judged by hybrid-arrested translation of alpha-amylase mRNAs in a cell-free system. Reconstruction experiments indicated that the levels of extended primers (determined by scintillation counting) were directly proportional to the level of input mRNA over a wide range. This indicates that the technique is suitable for quantification of relative levels of individual alpha-amylase from approximately 2% to 100% of maximal levels. The nucleotide sequences of extended primers defined two different alpha-amylase mRNAs in each of the low-pI and high-pI groups, and possibly a third mRNA in the high-pI group.

Base Sequence↗

PubMed1980

Ocular penetration of beta-adrenergic blocking agents. An experimental study with atenolol, metoprolol, timolol and propranolol.

A comparison was made between the ocular penetration of topically applied 14C-atenolol, 14C-timolol, 14C-propranolol and 3H-metoprolol by means of liquid scintillation counting. Only one eye was treated, the fellow eye served as a control. Blood plasma levels were measured as well. We could detect a relationship between the ocular penetration and the degree of lipophilicity of the drugs used, as was to be expected. Drugs with a higher degree of lipophilicity penetrated more readily into the eye, whereas they also achieved higher blood plasma levels. Relatively high concentrations of atenolol were found in the nicitating membrane, thus reflecting its poor ocular penetration. The concentrations detected in the untreated eye were low and probably cannot explain the marked reduction in intraocular pressure observed after unilateral instillation of active beta-adrenergic blocking drugs, as for instance timolol. Our findings suggest that the ocular penetration of beta-adrenergic blocking agents on topical application only plays a minor part in their ocular hypotensive effect.

Adrenergic beta-Antagonists↗

PubMed1987

Blood flow in an experimental rat brain tumor by tissue equilibration and indicator fractionation.

The tissue equilibration technique (Kety) was compared with the indicator fractionation technique for the measurement of blood flow to normal brain and an experimental brain tumor in the rat. The tumor was a cloned astrocytic glioma implanted in the cerebral hemisphere of F-344 rats. I-125 Iodoantipyrine, using a rising infusion for one minute, was used for the tissue equilibration technique. C-14 butanol, injected as a bolus 8 seconds before sacrifice, was used for the indicator fractionation technique. Samples were assayed using liquid scintillation counting and the iodoantipyrine results were regressed against the butanol results. For normal tissue R = 0.832, SEE = 0.115 ml/g/min, and Slope = 0.626. For tumor R = 0.796, SEE = 0.070 ml/g/min, and Slope = 0.441. The iodoantipyrine tissue/blood partition coefficient for normal hemisphere (gray and white matter) was 0.861 +/-0.037 (SD) and for tumor was 0.876 +/-0.042. The indicator fractionation technique with C-14 butanol underestimated blood flow in a consistent manner, probably because of incomplete extraction, early washout of activity from tissue and from evaporation of butanol during processing. Our experiments revealed no differences between tumor and normal brain tissue that might invalidate the comparison of iodoantipyrine blood flow results in brain tumors and surrounding normal brain.

1-Butanol↗

PubMed1990

The heterogeneity of the neuronal distribution of exogenous noradrenaline in the rat vas deferens.

After loading of the incubated rat vas deferens with 0.2 mumol/l 3H-noradrenaline (followed by 100 min of wash-out with amine-free solution), the efflux of endogenous and exogenous compounds was determined by HPLC with electrochemical detection and by column chromatography with scintillation counting. Two different types of heterogeneity of labelling were found. The first one is due to the preferential labelling of varicosities close to the surface of the tissue, the second one to the preferential labelling of vesicles close to the surface of loaded varicosities. As diffusion distances within the tissue and within varicosities are then longer for endogenous than for exogenous amine and metabolites, the composition of spontaneous efflux of exogenous compounds differed from that for endogenous compounds. Because of preferential neuronal and vesicular re-uptake of endogenous noradrenaline, the percentage contribution by noradrenaline to overall efflux was: endogenous less than exogenous. While 3H-DOPEG was the predominant exogenous metabolite, DOPEG and MOPEG equally contributed to the "endogenous" efflux. Desipramine abolished the consequences of the first heterogeneity of labelling, i.e., it increased the efflux more for endogenous than for exogenous noradrenaline; moreover it decreased the efflux of 3H-DOPEG, but increased that of 3H-MOPEG. The reserpine-like compound Ro 4-1284, on the other hand, abolished the consequences of the second type of heterogeneity; it reduced the specific activity of "total efflux" (i.e., of the sum of noradrenaline + DOPEG + MOPEG) to the specific activity of the tissue noradrenaline. The degree of heterogeneity of labelling was reduced after inhibition of monoamine oxidase and also when the tissues were loaded with 2 or 20 mumol/l 3H-noradrenaline. It is proposed that the various "compartments" and "pools" of noradrenaline described in the literature reflect the two heterogeneities described here.

2H-Benzo(a)quinolizin-2-ol, 2-Ethyl-1,3,4,6,7,11b-↗

PubMed1991

Origin and renewal of the intrinsic glycoproteins of the aqueous humor.

Rabbits were injected either intravitreally or intra-aqueously with L-[3H]-fucose and killed at several intervals after the administration of this marker for glycoproteins. The aqueous humor, the vitreous body and the ciliary body were processed for radiometry (liquid scintillation counting), sodium dodecyl sulfate-poly-acrylamide gel electrophoresis (SDS-PAGE) and fluorography. Light microscopic autoradiography was carried out on semi-thin sections of the ciliary body and revealed intense activity in terms of the synthesis, migration and renewal of glycoproteins in the ciliary epithelium. The amount of unbound [3H]-fucose in the aqueous humor decreased sharply by 4 h, and the labeled glycoproteins were present only in very small quantities at 1 day after the intra-aqueous injection. When [3H]-fucose was injected intravitreally, unbound radiolabel could be detected in the aqueous humor for greater than 1 day and the labeled glycoproteins, for up to 21 days after injection. The amount of unbound or bound [3H]-fucose was higher in the vitreous than in the aqueous at any interval after the intravitreal injection. Following the intra-aqueous injection, the amount of label that reached the vitreous body was practically insignificant. The levels of radioactivity in the serum were extremely low, as they were in the contralateral eye when tritiated fucose was injected into one eye only. Most of the Coomassie blue-stained bands detected in SDS-PAGE contained labeled glycoproteins as revealed by fluorography of gels simultaneously containing aqueous and vitreous samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗