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PubMed2006

Effects of polyunsaturated fatty acids on calcium response and degranulation from RBL-2H3 cells.

To investigate the biological activity of various polyunsaturated fatty acids (PUFAs) on the allergic reaction, we examined the effects of six PUFAs and two saturated fatty acids on calcium response and degranulation from rat basophilic leukemia (RBL-2H3) cells. Between 20 and 40 microM of six PUFAs (omega-6 series: arachidonic acid [AA, C20:4], gamma-linolenic acid [gamma-LN, C18:3] and linoleic acid [LA, C18:2]; omega-3 series: alpha-linolenic acids [alpha-LN, C18:3] and eicosapentaenoic acid [EPA, C20:5]; and omega-9 series: oleic acid [OLE, C18:1]), or two saturated fatty acids (stearic acid [STA, C18:0] and arachidic acid [AD, C20:0]) were used to examine the effects on calcium response and degranulation from RBL-2H3 cells. Calcium response was monitored using the fluorescent calcium indicator fura-2, while degranulation was monitored by measuring histamine release from the cells. Three omega-6 PUFAs (AA, alpha-LN and LA) dose-dependently increased the cytosolic free-calcium concentration and histamine release from RBL-2H3 cells. This phenomenon was specific to the omega-6 PUFAs, the omega-3 PUFAs (alpha-LA and EPA), omega-9 PUFA (OLE) and the saturated fatty acids (STA and AD) had no effect. The increase in the cytosolic free-calcium concentration caused by the omega-6 PUFAs depended on the existence of external calcium, cell viability and the cellular IP(3) levels remained unchanged throughout the experiment. These results suggest that omega-6 PUFAs work as direct mediators of calcium signaling pathways in RBL-2H3 cells.

Animals↗

PubMed2006

Wettability of calcite and mica modified by different long-chain fatty acids (C18 acids).

The effect of long-chain fatty acid adsorption on the wetting states of calcite and mica powders is investigated. The selected long-chain fatty acids are saturated or unsaturated aliphatic acids (stearic acid and oleic acid, respectively) and naphthenic acids with saturated or unsaturated aromatic rings (18-cyclohexyloctadecanoic acid and 18-phenoloctadecanoic acid, respectively). The amount of irreversibly adsorbed acid is determined by thermogravimetric analysis. The affinity of water and n-decane for these samples before and after modification is deduced from their adsorption isotherm and microcalorimetry. Thermodynamic analysis of surface pressure and spreading tension are performed based on adsorption isotherms. The enthalpy versus coverage curve for water adsorption and its comparison to liquefaction enthalpy is shown to be a meaningful method for characterizing the wettability of a surface. The naphthenic acid with unsaturated aromatic ring deeply modifies the calcite to an oil-wet state. The mica powder was not as strongly modified as calcite by these acid molecules.

Journal Article↗

PubMed1995

Effect of non-lytic concentrations of Brij series detergents on the metabolism-independent ion permeability properties of human erythrocytes.

Subcritical micellar concentrations (sub-CMC) of Brij-series detergents alter ion movements between human erythrocytes and their environment when metabolism has been slowed down by incubation at zero degrees centigrade. The effect of nonhemolytic concentrations of detergents on the erythrocyte K+ and Na+ movements is described. Results indicate a significant difference in monovalent cation movements, depending on the number of hydrophilic polyoxyethylene units (n). There is an increasing loss of K+ and gain of Na+ as n increases from 4 to 20. Where n > or = 21, ion movements are not significantly different from those found in erythrocytes not exposed to detergents. The carbon chain length of the detergent fatty acid residue (10-18 carbons) appears to be relatively unimportant, but detergents with unsaturated (oleic acid) hydrophobic regions potentiate K+ release and Na+ uptake when compared to the corresponding saturated fatty acid (stearic acid). The erythrocyte stabilizing effect of detergents against hypo-osmotic shock correlates well with the increase of monovalent ion traffic and the mobility of membrane lipids revealed by fluorescence anisotropy measurements.

Adenosine Triphosphate↗

PubMed1997

A single-residue deletion alters the lipid selectivity of a K+ channel-associated peptide in the beta-conformation: spin label electron spin resonance studies.

Lipid-peptide interactions with the 27-residue peptide of sequence KLEALYILMVLGFFGFFTLGIMLSYIR reconstituted as beta-sheet assemblies in dimyristoylphosphatidylcholine bilayers have been studied by electron spin resonance (ESR) spectroscopy with spin-labeled lipids. The peptide corresponds to residues 42-68 of the IsK voltage-gated K+ channel protein and contains the single putative transmembrane span of this protein. Lipid-peptide interactions give rise to a second component in the ESR spectra of lipids spin-labeled on the 14C atom of the chain that corresponds to restriction of the lipid mobility by direct interaction with the peptide assemblies. From the dependence on the lipid/peptide ratio, the stoichiometry of lipid interaction is found to be about two phospholipids/peptide monomer. The sequence of selectivity for lipid association with the peptide assemblies is in the order phosphatidic acid > stearic acid = phosphatidylserine > phosphatidylglycerol = phosphatidylcholine. Comparison with previous data for a corresponding 26-residue mutant peptide with a single deletion of the apolar residue Leu2 (Horvath et al., 1995. Biochemistry 34:3893-3898), indicates a very similar mode of membrane incorporation for native and mutant peptides, but a strongly modified pattern and degree of specificity for the interaction with negatively charged lipids. The latter is interpreted in terms of the relative orientations of the charged amino acid side chains in the beta-sheet assemblies of the native and deletion-mutant peptides.

Amino Acid Sequence↗

PubMed2001

Effect of fatty acids on phase behavior of hydrated dipalmitoylphosphatidylcholine bilayer: saturated versus unsaturated fatty acids.

The effect of some fatty acids on the phase behavior of hydrated dipalmitoylphosphatidylcholine (DPPC) bilayer was investigated with special interest in possible difference between saturated and unsaturated fatty acids. The phase behavior of hydrated DPPC bilayer was followed by a differential scanning calorimetry and a Fourier transform infrared spectroscopy. The addition of palmitic acid (PA) increased the bilayer phase transition temperature with the increase of the PA content in the mixture. In addition, DPPC molecules in gel phase bilayer became more rigid in the presence of PA compared with those in the absence of PA. This effect of PA on the phase behavior of hydrated DPPC bilayer is common to other saturated fatty acids, stearic acid, myristic acid, and also to unsaturated fatty acid with trans double bond, elaidic acid. Contrary to these fatty acids, oleic acid (OA), the unsaturated fatty acid with cis double bond in the acyl chain, exhibited quite different behavior. The effect of OA on the bilayer phase transition temperature was rather small, although a slight decrease in the temperature was appreciable. Furthermore, the IR spectral results demonstrated that the perturbing effect of OA on the gel phase bilayer of DPPC was quite small. These results mean that OA does not disturb the hydrated DPPC bilayer significantly.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1998

The effect of arachidonic acid and free fatty acids on vesicular uptake of glutamate and gamma-aminobutyric acid.

The manner in which arachidonic acid and other free fatty acids influence the vesicular uptake of glutamate and gamma-aminobutyric acid (GABA) has been investigated. The cis-polyunsaturated fatty acid arachidonic acid (20:4), eicosapentanoic acid (20:5) and linolenic acid (18:3) at 150 nmol/mg protein (50 microM) inhibited the vesicular uptake of glutamate and GABA more than 70%. Reduced inhibition of vesicular uptake was seen with the cis-monounsaturated fatty acid oleic acid (18:1) and the trans-mono-unsaturated fatty acid elaidic acid (18:1). The saturated fatty acids stearic acid (16:0) and arachidic acid (20:0) had no significant effect on the uptake. The inhibition of vesicular uptake by arachidonic acid was prevented by the addition of fatty acid free bovine serum albumin. Arachidonic acid inhibited in a dose-dependent manner the generation of the transmembrane pH gradient of the synaptic vesicles. This inhibition was proportional to the inhibition of the vesicular uptake of glutamate and GABA. The saturated fatty acid arachidic acid showed no inhibition of delta pH generation. Arachidonic acid at 200 nmol/mg of protein did not increase the uptake-independent leakage of glutamate and GABA from the vesicles, showing that the effect of arachidonic acid is not caused by an unspecific detergent effect. These results suggest that arachidonic acid and other polyunsaturated fatty acids are acting like proton-ionophores on the vesicular uptake of these neurotransmitters. This finding may have implications for the increased fatty acid concentration during pathological conditions like ischemia and in long term potentiation.

Animals↗

PubMed2002

Analysis of free and bound volatiles by gas chromatography and gas chromatography-mass spectrometry in uncased and cased tobaccos.

The free and bound volatiles of tobaccos were analyzed by capillary GC and GC-MS. Bound volatiles were isolated by dichloromethane extraction followed by stream distillation continuous extraction (SDE) at pH 2.5 acid hydrolysis. The bound aromatic compounds were hydrolyzed by acid at pH 2.5, and the bound volatiles were liberated and extracted into dichloromethane by SDE simultaneously. In total, 23 volatiles were identified, with neophytadiene, 2-ethyl hexanol, damascenone, benzene ethanol, palmitic acid, stearic acid, linoleic acid, farnesyl acetone, 3-oxo-ionol, and megastigmatrienone being the major components. They consisted mainly of compounds exhibiting aromatic characteristics. The quality and quantity of free and bound volatiles exhibited different distributions in uncased or cased tobaccos. The volatiles existed in higher amounts in bound form than in free form. Compared with uncased tobaccos, free form volatiles showed a decrease after the casing process, while bound volatiles showed an increase.

Chromatography, Gas↗

PubMed1989

Saturation of fat and cholecystokinin release: implications for pancreatic carcinogenesis.

In a study to determine the effect of saturation of fats on their ability to stimulate cholecystokinin (CCK) release six normal volunteers ate five test meals containing different fats with intervals of 1 week. Plasma CCK levels were measured by a specific radioimmunoassay and the gallbladder volume was calculated from ultrasound measurements. The sodium salt of the monounsaturated fatty acid oleic acid (3.5 g) produced a significantly greater integrated CCK response than that of the saturated fatty acid stearic acid (mean [SEM] 103 [41] vs 8[41] pmol.l-1.min). The gallbladder contracted to 42 (3)% of its initial volume after oleate but remained at 89 (8)% of its initial volume after stearate. Integrated CCK responses to dietary triglycerides (30 g) also differed significantly according to the degree of saturation--277 (58) pmol.l-1.min after corn oil (predominantly diunsaturated), 143 (14) pmol.l-1.min after olive oil (predominantly monounsaturated), and 44 (12) pmol.l-1.min after suet (predominantly saturated). The finding that unsaturated fats are stronger stimulants of CCK release than saturated fats may explain the promotion of pancreatic carcinogenesis in rats by unsaturated but not saturated fats and may support the role of CCK in this effect.

Adult↗

PubMed1998

Compatibility study between ibuproxam and pharmaceutical excipients using differential scanning calorimetry, hot-stage microscopy and scanning electron microscopy.

Differential scanning calorimetry (DSC) was used as a screening technique for assessing the compatibility of ibuproxam with some currently employed pharmaceutical excipients. The influence of processing effects (simple blending, cogrinding or kneading) on drug stability was also evaluated. On the basis of DSC results, ibuproxam was found to be compatible with corn starch, avicel and sodium carboxymethylcellulose. Some drug-excipient interaction was observed with polyethyleneglycol 4000, palmitic acid, stearic acid, Ca and Mg stearate. Actual solid-phase interactions of the drug with polyvinylpolypyrrolidone and polyvinylpirrolidone K30 were induced by mechanical treatments. Hot-stage microscopy (HSM) and scanning electron microscopy (SEM) were of help in interpreting the DSC results and excluding in all cases relevant pharmaceutical incompatibilities.

Benzeneacetamides↗

PubMed2002

Ranking the toxicity of fatty acids on Jurkat and Raji cells by flow cytometric analysis.

The fatty acids have an important role in the control of leukocyte metabolism and function. Higher concentrations of certain fatty acids, particularly polyunsaturated fatty acids (PUFAs) and volatile fatty acids, can cause cell death via apoptosis or, when concentrations are greater, necrosis. In this study, we determined the highest concentrations of various fatty acids that are non-toxic to two human leukemic cell lines, Jurkat (T-lymphocyte) and Raji (B-lymphocyte). Toxicity was evaluated by either loss of membrane integrity and/or DNA fragmentation using flow cytometric analysis. There were no remarkable differences for the toxicity of the fatty acids between B and T cell lines. The cytotoxicity of the fatty acids was related to the carbon chain length and number of double bonds: docosahexaenoic acid=eicosapentaenoic acid=arachidonic acid=gamma-linolenic acid=stearic acid=palmitic acid > linoleic acid=palmitoleic acid > vacenic acid=lauric acid > oleic acid > elaidic acid > capric acid > butyric acid > caprylic acid=caproic acid=propionic acid. The proportion of cells undergoing apoptosis or necrosis, induced by the fatty acids tested, remains to be investigated.

Apoptosis↗

PubMed2003

Long-chain polyunsaturated fatty acids and chemically induced diabetes mellitus: effect of omega-6 fatty acids.

OBJECTIVE: We previously showed that prior oral supplementation of oils rich in omega-3, eicosapentaenoic acid and docosahexaenoic acid, and omega-6, gamma-linolenic acid and arachidonic acid, can prevent the development of alloxan-induced diabetes mellitus in experimental animals. But the effect of individual fatty acids on chemically induced diabetes mellitus is not known. We report the results of our studies with omega-6 fatty acids. METHODS: Alloxan-induced in vitro cytotoxicity and apoptosis in an insulin-secreting rat insulinoma cell line, RIN, was prevented by prior exposure of these cells to linoleic acid, gamma-linolenic acid, and arachidonic acid (AA) but not to dihomo-gamma-linolenic acid. Cyclo-oxygenase and lipoxygenase inhibitors did not block this protective action of AA. Prior oral supplementation with gamma-linolenic acid and pre- and simultaneous treatments with AA prevented alloxan-induced diabetes mellitus. RESULTS: Even though pretreatment with linoleic acid and dihomo-gamma-linolenic acid and simultaneous treatment with linoleic acid, gamma-linolenic acid, and dihomo-gamma-linolenic acid did not prevent the development of diabetes mellitus, the severity of diabetes was much less. The saturated fatty acid stearic acid and the monounsaturated fatty acid oleic acid were ineffective in preventing alloxan-induced diabetes mellitus. gamma-Linolenic acid and AA not only attenuated chemically induced diabetes mellitus but also restored the antioxidant status to normal range in various tissues. Changes in the concentrations of various fatty acids of the phospholipid fraction of plasma that occurred as a result of alloxan-induced diabetes mellitus also reverted to normal in the AA-treated animals. CONCLUSIONS: These results suggest that polyunsaturated fatty acids can prevent chemically induced diabetes in experimental animals and attenuate the oxidant stress that occurs in diabetes mellitus.

Alloxan↗

PubMed2000

Membrane fluidity changes are associated with the antiarrhythmic effects of docosahexaenoic acid in adult rat cardiomyocytes.

Previous studies using neonatal rat cardiomyocytes have reported antiarrhythmic effects of long-chain polyunsaturated fatty acids (PUFAs). In this study, we examined the effects of the n-3 polyunsaturated fatty acid docosahexaenoic acid (DHA) on the spontaneous contractile activity and membrane fluidity of adult rat ventricular myocytes. Cardiomyocytes were induced to contract spontaneously by continuous superfusion of a solution containing the arrhythmogenic agents isoproterenol (a beta-adrenergic receptor agonist) or lysophosphatidylcholine. The percentage of cardiomyocytes displaying spontaneous contractions induced by isoproterenol when pretreated with the saturated fatty acid docosanoic acid was 48.1 +/- 7.7%; the percentage for cardiomyocytes pretreated with DHA was 7.1 +/- 2.4% (P < 0.01). DHA significantly prevented lysophosphatidylcholine-induced spontaneous contractions (17.7 +/- 6.5%) compared with treatment with the saturated fatty acid stearic acid (78.0 +/- 7.3%, P < 0.01). The membrane fluidizing agent benzyl alcohol also significantly prevented spontaneous contractions in cardiomyocytes. Membrane fluidity was determined by steady-state fluorescence anisotropy (r(ss)) using the fluorescent probe N-((4-(6-phenyl-1,3,5-hexatrienyl)phenyl)propyl) trimethyl-ammonium p-toluene-sulfonate (TMAP-DPH). DHA and benzyl alcohol dose-dependently decreased the r(ss); however, saturated fatty acids were without effect. These results suggest that the antiarrhythmic mechanisms of the n-3 PUFAs such as DHA may involve changes in membrane fluidity.

Journal Article↗

PubMed1998

Biomimetic processing of calcium phosphate coating.

Most ceramics used in surgical implantation are better tolerated by the body environment than other biomaterials, particularly metals. However, the broader application of ceramics is limited because they are brittle and prone to catastrophic failure. By contrast. naturally produced ceramic organic biocomposites can possess mechanical properties which make them suitable for use as biomaterials. An example would be the mollusc shell, where an inorganic phase grows onto a charged and organised organic template. This natural biomineralization provides a calcium carbonate phase with satisfactory mechanical properties appropriate for surgical implantation. It is reported how Langmuir Blodgett films have been used as organic templates for calcium phosphate crystallization. Three different Langmuir Blodgett Films: omega tricosenoic acid, stearic acid and octadecylamine have been investigated. The Langmuir Blodgett Films produced had methyl (CH3) and calcium carboxylate (CaCOO) as functional groups. Atomic force microscopy and scanning electron microscopy shows that calcium phosphate crystallization occurs in a similar manner to natural biomineralization. The calcium carboxylate head group appears to have a physical influence on the morphology and distribution of the calcium phosphate crystals. Under the experimental conditions tested, the calcium carboxylate functional head group controls calcium phosphate crystallization by a biomimetic approach. This study strongly suggests that this approach has the potential for producing high performance ceramics comparable with those made by mollusc shells.

Calcium Phosphates↗

PubMed1995

Integration of a K+ channel-associated peptide in a lipid bilayer: conformation, lipid-protein interactions, and rotational diffusion.

The 26-residue peptide of sequence KEALYILMVLGFFGFFTLGIMLSYIR, which contains the single putative transmembrane domain of a small protein that is associated with slow voltage-gated K+ channels, has been incorporated in bilayers of dimyristoylphosphatidylcholine by dialysis from 2-chloroethanol to form complexes of homogeneous lipid/peptide ratio. Fourier transform infrared spectroscopy indicates that the peptide is integrated in the lipid bilayer wholly in a beta-sheet conformation. The electron spin resonance spectra of spin-labeled lipids in the lipid/peptide complexes contain a component corresponding to lipids whose chains are motionally restricted in a manner similar to those of lipids at the hydrophobic surface of integral transmembrane proteins. From the dependence of the lipid spin label spectra on the lipid/peptide ratio of the complexes, it is found that ca. 2.5 lipids per peptide monomer, independent of the species of spin-labeled lipid, are motionally restricted by direct interaction with the peptide in the bilayer. This value would be consistent with, e.g., a beta-barrel structure for the peptide in which the beta-strands either are strongly tilted or have a reverse turn at their center. A preferential selectivity of interaction with the peptide is observed for the negatively charged spin-labeled lipids phosphatidic acid, stearic acid, and phosphatidylserine, which indicates close proximity of the positively charged residues at the peptide termini to the lipid headgroups. The saturation-transfer electron spin resonance spectra of the peptide spin-labeled at a cysteine residue replacing Leu18 evidence rather slow rotational diffusion in the lipid complexes.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

PubMed1986

Purification and initial characterization of the 71-kilodalton rat heat-shock protein and its cognate as fatty acid binding proteins.

The major rat heat-shock (stress) protein and its cognate were purified to electrophoretic homogeneity from livers of heat-shocked rats. Both proteins exhibited similar behavior on a variety of column chromatography matrices but were separable by preparative isoelectric focusing under nondenaturing conditions by virtue of a 0.2 pH unit difference in isoelectric point. Both purified proteins had similar physical properties, suggesting the possibility that they may have similar biological functions as well. Both proteins were homodimers under nondissociative conditions (Mr 150 000) with isoelectric points of 5.0 (cognate) and 5.2 (major stress protein). After denaturation, both proteins had an increase in isoelectric point of 0.6 pH unit, and the resulting polypeptide chains had apparent molecular weights of 73 000 (cognate) and 71 000 (major stress protein). Similarities in the electrophoretic properties of these two proteins and serum albumin, which also undergoes a large basic shift in isoelectric point due to loss of fatty acids and conformational changes accompanying denaturation, prompted us to search for lipids associated with the purified 71-kilodalton stress protein and its cognate. Thin-layer chromatography of chloroform/methanol extracts of these two proteins revealed nonesterified fatty acids bound to both proteins. Palmitic acid, stearic acid, and a small amount of myristic acid were identified by gas chromatography/mass spectroscopy. Both proteins contained approximately four molecules of fatty acid per dimer with palmitate and stearate present in a one to one molar ratio. Possible roles of the major stress protein and its cognate as fatty acid associated proteins in cellular responses to stress are discussed.

Animals↗

PubMed1966

Changes in lipid composition of the maturing rat testis.

1. The lipids and fatty acids of the lipids of testes of rats aged 4 weeks to 6 months were separated and analysed. 2. A decrease in concentration of triglyceride was noted, but there was no significant change in the concentration of phospholipids, plasmalogen or cholesterol during this time. 3. There were no significant differences in the total lipid concentration of palmitic acid, stearic acid, linoleic acid, arachidonic acid and docosatetraenoic acid between the various age groups. 4. A decrease in the concentration of oleic acid in the phosphatide and triglyceride fractions and an increase in the concentration of docosapentaenoic acid (characterized as the Delta4,7,10,13,16-isomer) in phosphatides but not in triglyceride were observed during the maturation period. 5. Histological studies indicated that the lipid changes occurred at the same time as the appearance and maturation of the spermatids.

Animals↗

PubMed1966

Fatty acid composition of the plasma lipids of newborn and maternal ruminants.

1. The fatty acid compositions of the plasma lipids of newborn unsuckled lambs, kids, calves and piglets have been determined and compared with those of maternal plasma lipids at parturition. 2. The predominating plasma fatty acids in the newborn of all species are palmitic acid, C(16:1) acid, stearic acid and C(18:1) acid. This finding is consistent with the synthesis of the major proportion of fatty acids from non-lipid sources within the foetus. 3. Very small amounts of C(18:2) acid and C(18:3) acid are present in the plasma lipids of newborn ruminants, although considerable amounts of these fatty acids are contained in maternal plasma. The plasma fatty acids of the newborn piglet contained 5.5% of C(18:2) acid, those of the calf 2.0%, and those of the lamb and kid less than 1.0%. This finding is discussed in relation to the higher content of C(18:2) acid in the plasma non-esterified fatty acid fraction of the sow (15%) compared with that of the ruminant (less than 4%). 4. In the lamb and kid, but not in the calf or piglet, a C(20:3) acid was detected in plasma lipids that was very similar to, if not identical with, the C(20:3) acid that accumulates in the plasma of animals given diets low in essential fatty acids. The possible significance of this finding is discussed. 5. The cholesteryl esters of cow plasma were found to contain a higher percentage (43%) of C(18:3) acid than those of goat and sheep plasma (5-10%). The possible reasons for this difference are discussed.

Animals↗

PubMed1971

Chemical composition of an oestrogen-induced calcium-binding glycolipophosphoprotein in Xenopus laevis.

1. Oestrogen treatment has previously been shown to induce the formation of large amounts of a serum protein, vitellogenin (xenoprotein), in Xenopus laevis. Vitellogenin was purified from serum by dimethylformamide precipitation and was shown to be homogeneous by a variety of electrophoretic techniques. 2. The molecular weight of vitellogenin was estimated by gel filtration to be about 6x10(5). The chemical constituents of vitellogenin were determined and lead to the characterization of this protein as a serum calcium-binding glycolipophosphoprotein. 3. The extractable lipid accounted for 12% of vitellogenin. Gas-liquid-chromatographic analysis of the saponified lipid moiety showed the presence of palmitic acid, palmitoleic acid, stearic acid, oleic acid and linoleic acid in the molecular proportions 6.8: 1.5: 1.0: 3.6: 1.4. 4. The carbohydrate moiety consisted of 0.4g of hexose, 0.77g of hexosamine and 0.18g of sialic acid/100g of vitellogenin. 5. The calcium and phosphorus contents were 0.85 and 1.65g/100g of vitellogenin respectively. 6. Serum from oestrogen-treated animals injected with (45)CaCl(2) contained 9.7 times the radioactivity present in serum from untreated (45)CaCl(2)-injected animals. Of the radioactivity due to (45)CaCl(2) in the serum of oestrogen-treated animals 72% was non-diffusible on dialysis. Of this activity 65.4% was associated with the vitellogenin band on cellulose acetate electrophoresis.

Animals↗