Bradykinin-stimulated release of arachidonate from phosphatidyl inositol in mouse fibrosarcoma cells

We recently proposed a new pathway by which arachidonate is released from platelet phosphatidyl inositol after stimulation by either thrombin or calcium ionophore A23187. The initial step in arachidonate liberation involves hydrolysis of phosphatidyl inositol to form 1,2-diacylglycerol which is subsequently hydrolyzed by a diacylglycerol lipase to liberate arachidonate for the prostaglandin and lipoxygenase pathways. Whether this pathway is unique to platelets or accounts for arachidonate release from other tissues has not been previously studied. Thus we have now investigated arachidonate metabolism in mouse fibrosarcoma cells (HSDM₁C₁) grown in culture. These cells contain approximately 7.6% of their total phospholipid as phosphatidyl inositol in the resting state (range 6.5–8.3%). When bradykinin (12 μM) is added to the fibrosarcoma cells, there is a rapid depletion of membrane phosphatidyl inositol reaching 62 ± 8% S.D. of baseline values by 15 seconds, falling to 36 ± 6% by 15 minutes. The drop in membrane phosphatidyl inositol is accompanied by release of arachidonate and PGE₂ into the culture medium. The time course of phosphatidyl inositol breakdown and PGE₂ formation supports the idea that phosphatidyl inositol breakdown provides the arachidonate for prostaglandin synthesis in mouse fibrosarcoma cells. Crude extracts of HSDM₁C₁ cells contained sufficient phosphatidyl inositol-specific phospholipase C activity and diacylglycerol lipase activity to account for arachidonate release in these cells.     

Effects of lipids on the activity of soluble mitochondrial pyrophosphatase and its conversion to the membrane-bound form

The effects of lipids on the activity of soluble and membrane-bound pyrophosphatase from beef heart mitochondria were studied. An addition of total mitochondrial lipid, phosphatidyl choline, phosphatidyl ethanolamine or cardiolipin resulted in stimulation of the enzymatic activity and an increase in thermal stability of the soluble enzyme. The maximal activating effect was exerted by the total mitochondrial lipid and phosphatidyl choline. The electrophoretic data suggest that phosphatidyl choline is a component of membrane pyrophosphatase. Preincubation of the soluble enzyme with phosphatidyl choline converted the enzyme into a membrane form, which is capable to carry out the energy-dependent synthesis of PPi in submitochondrial particles.     

METABOLIC RELATIONSHIPS BETWEEN MYELIN SUBFRACTIONS: ENTRY OF GALACTOLIPIDS AND PHOSPHOLIPIDS 1

Abstract— Partially purified myelin from the brains of 17-day-old rats was separated into 4 subfractions on a three-step sucrose gradient by virtue of heterogeneity in density and particle size. Precursor-product relationships between different membrane fractions were investigated by determining the specific radioactivity of individual lipids in each subcellular fraction 15 min after intracranial injection of an appropriate precursor. Rats were injected with [2-³H]glycerol. myelin subfractions prepared, and individual lipids separated by TLC. For choline and ethanolamine phospholipids, specific radioactivity was highest in the densest fraction (D), intermediate in the next densest fraction (C), and lowest in the lighter fractions (B and A). Similar results were observed for cerebroside and sulphatide when [³H]galactose was the precursor. These data are consistent with (but do not prove) a precursor-product relationship for individual lipids from the densest to the lightest subfraction. Another experimental design involving time staggered injections of [³H] and [¹⁴C] precursors was developed which enables a more definitive result with regard to precursor-product relationships to be obtained. A precursor-product relationship between a given lipid in a dense myelin membrane fraction, and the same lipid in a lighter subfraction, would be indicated by a change in isotope ratio. If there is no precursor-product relationship. Ihe isotope ratio should be constant. Such experiments were done with [³H] and [¹⁴C]glycerol. The data indicated that phosphatidyl ethanolamine and its plasmalogen analog were added first to the densest subfraction and then in turn to the lighter subfractions. In contrast, phosphatidyl choline and its plasmalogen analog were added “simultaneously” (i.e. with delays of much less than 15min) to each of the subfractions. Similar experiments with [³H] and [¹⁴C]galactose showed that cerebroside, sulphatide and galactosyl diglyceride also entered the subfractions simultaneously rather than in sequential order. Thus the assembly of the myelin sheath involves an obligate order of addition of certain lipids. while other lipids are probably added in a random order.     

Effect of Low Temperature upon Lipid and Fatty Acid Composition of Roots and Leaves of Winter Rape Plants

When winter rape plants were transferred from favourable temperature conditions (25/20°C day/night temperature) to 5°C, the frost resistance of the leaves was increased whereas the frost tolerance of the roots remained unaffected. This permitted an analysis of the changes in lipid and fatty acid composition both as related to functioning of the plant at low temperature alone (roots) and as related to adaptation to freezing and functioning at low temperature (leaves). — Transfer of the plants to 5°C lead to an increase in the level of linolenic acid in roots and leaves. This increase was most evident in the phosphatidyl choline and ethanolamine fractions of the leaves, and in the neutral lipids and in an unidentified phospholipid from the roots. It was concluded that upon transfer of the plants to 5°C a general and non-specific increase in linolenic acid level contributed to functioning of the rape plants at low temperature; and that parallel but minor increases in linolenic acid level of digalactosyl diglyceride, phosphatidyl inositol and the unknown phospholipid in roots and leaves could only contribute to low-temperature functioning in specific membrane enzyme locations. Combined adaptation of the leaves to freezing tolerance and low-temperature functioning was correlated with a higher level of phosphatidyl choline and ethanolamine, predominantly esterified with linolenic acid.     

Translocation and turnover of phospholipid analogs in plasma membrane-derived vesicles from cell cultures.

The time-dependent accumulation of phosphatidyldimethylethanolamine in formaldehyde-induced vesicles obtained from a somatic cell hybrid line was investigated. From a number of considerations including a two-fold enrichment of cholesterol and sphingomyelin it was concluded that these vesicles were derived from the cell plasma membrane. A progressive depletion of phosphatidylcholine, the major vesicle phospholipid, was observed in cells supplemented for various time periods with dimethylethanolamine. This depletion was accompanied by a concomitant increase in the amount of lipid analog. The time-dependent alteration of the phospholipid polar head group in intact cells was almost identical to that observed in isolated plasma membrane vesicles, suggesting a rapid equilibration of the de novo synthesized phospholipid with the cell surface compartment. From the initial velocity rate, the time required for the phosphatidylcholine pool to double was about 12 h. Agarose-linked phospholipase A2 was used to measure the relative composition of choline- and dimethylethanolamine-phosphoglycerides in the outer surface of vesicles prepared from cells with different degrees of polar head group substitution. The gradual appearance of lysodimethylethanolamine lipid analog in vesicles treated with phospholipase A2 suggested an asymmetric distribution of the phospholipid between the interior and the exterior part of the vesicle. This asymmetry was maximal up to about 4 h following the addition of dimethylethanolamine to the culture medium and was of a transient nature as the lipid analog accumulated on both sides of the plasma membrane. Based on these measurements a fast followed by a slow translocation component could be distinguished with apparent doubling times of 7 and 43 h for the lipid analog, respectively. As the analog becomes the predominant cellular phospholipid a significant increase in the vesicle lipid fluidity was measured.     

Translocation and turnover of phospholipid analogs in plasma membrane-derived vesicles from cell cultures

The time-dependent accumulation of phosphatidyldimethylethanolamine in formaldehyde-induced vesicles obtained from a somatic cell hybrid line was investigated. From a number of considerations including a two-fold enrichment of cholesterol and sphingomyelin it was concluded that these vesicles were derived from the cell plasma membrane.A progressive depletion of phosphatidylcholine, the major vesicle phospholipid, was observed in cells supplemented for various time periods with dimethylethanolamine. This depletion was accompanied by a concomitant increase in the amount of lipid analog.The time-dependent alteration of the phospholipid polar head group in intact cells was almost identical to that observed in isolated plasma membrane vesicles, suggesting a rapid equilibration of the de novo synthesized phospholipid with the cell surface compartment. From the initial velocity rate, the time required for the phosphatidylcholine pool to double was about 12 h.Agarose-linked phospholipase A₂ was used to measure the relative composition of choline- and dimethylethanolamine-phosphoglycerides in the outer surface of vesicles prepared from cells with different degrees of polar head group substitution. The gradual appearance of lysodimethylethanolamine lipid analog in vesicles treated with phospholipase A₂ suggested an asymmetric distribution of the phospholipid between the interior and the exterior part of the vesicle. This asymmetry was maximal up to about 4 h following the addition of dimethylethanolamine to the culture medium and was of a transient nature as the lipid analog accumulated on both sides of the plasma membrane. Based on these measurements a fast followed by a slow translocation component could be distinguished with apparent doubling times of 7 and 43 h for the lipid analog, respectively. As the analog becomes the predominant cellular phospholipid a significant increase in the vesicle lipid fluidity was measured.     

Lipid monolayers: action of phospholipase A of Crotalus atrox and Naja naja venoms on phosphatidyl choline and phosphatidal choline

The activity of phospholipase A on phosphatidyl choline and phosphatidal choline spread as monolayers on phosphate buffers containing snake venom (Crotalus atrox or Naja naja) was studied by measuring the fall of surface potential as a function of time, pH, film pressure, temperature, and concentrations of phosphate and venom. At 25 degrees C, pH 7.0, and 0.2 micrograms of venom per ml, optimal activity was observed with both venoms on both substrates at 12 dynes/cm film pressure on 0.04 m phosphate. Under these conditions, the pH optimum for C. atrox was broad (6.6-7.4) and that for N. naja was sharp (8.0) for the action on phosphatidyl choline, whereas both venoms had a sharp optimum at pH 8.0 in their action on phosphatidal choline. The optimal temperature with phosphatidyl choline was 27.5 degrees C for N. naja and 40 degrees C for C. atrox. In line with studies of phospholipase A activity in bulk phase in ether, phosphatidal choline was attacked much more slowly than phosphatidyl choline by C. atrox. Under conditions where both venoms had equal activity on phosphatidyl choline, C. atrox was only half as active as N. naja on phosphatidal choline. The studies suggest that the linkage of the hydrophobic chains in glycerophosphatides may affect their interaction with proteins.     

The manipulation of polar head group composition of phospholipids in the wheat Miranovskaja 808 affects frost tolerance

Caryopses of the frost-resistant cultivar of the wheat Triticum aestivum L., Miranovskaja 808, were germinated and grown in the presence of various concentrations of choline chloride. Changes in the composition of leaf total phospholipids and leaf total fatty acids at two extreme temperatures (25°C and 2°C) as well as changes in frost resistance were followed. A choline chloride concentration-dependent accumulation of phosphatidyl choline was observed in the leaves. Seedlings grown at 2°C accumulated more phosphatidyl choline at each choline chloride concentration than those grown at 25°C. There was an inverse relationship between the contents of phosphatidyl choline and phosphatidic acid in the leaves. Neither the temperature nor choline chloride seemed to affect fatty-acid composition. Modification of polar-head group composition of phospholipids affected frost tolerance: Seedlings grown in the presence of 15 mM choline chloride at 25°C exhibited a freezing resistance equal to that of hardened controls. The data indicate that the polar-head group composition of membrane phospholipids in plants can be easily manipulated and point to the importance of phosphatidyl choline in cold adaptation processes.     

Asymmetric distribution of phospholipids in membranes from Mycobacterium phlei

The distribution of phospholipids in the membranes of Mycobacterium phlei has been studied by the use of phospholipase C and trinitrobenzenesulfonic acid. In inverted membrane vesicles, whose external surface apparently corresponds topologically to the cytoplasmic surface of the membrane in intact cells, 80% of the phosphatidyl ethanolamine, 24% of diphosphatidyl glycerol, and 13% of phosphatidyl inositol are accessible to cleavage by phospholipase C. These results are in agreement with the finding that 70–75% of phosphatidyl ethanolamine in the membrane is accessible to chemical modification by trinitrobenzenesulfonic acid or dimethylsuberimidate at 4 °C. It can be inferred that in the inverted membrane the majority of phosphatidyl ethanolamine is present on the outer half of the lipid bilayer while inner half constitutes primarily other phospholipids namely phosphatidyl inositol and diphosphatidyl glycerol. Phospholipase C treatment of ETP membranes selectively impairs the active transport of Ca²⁺ without affecting the generation of a proton gradient, respiration, and coupled phosphorylation.     

Delayed activation of phospholipase D by gonadotropin-releasing hormone in a clonal pituitary gonadotrope cell line (alpha T3-1).

Stimulation of cultured pituitary cells from a gonadotrope lineage (alpha T3-1) by the gonadotropin-releasing hormone agonist analog [D-Trp6]GnRH (GnRH-A) resulted in a manifold increase in accumulation of phosphatidylethanol, a specific product of phospholipase D phosphatidyl transferase activity when ethanol is the phosphatidyl group acceptor. Levels of the natural lipid product of phospholipase D, phosphatidic acid, were increased 2-3-fold. Activation of phospholipase D by GnRH-A was dose- and time-dependent and was blocked by a GnRH receptor antagonist [D-pClPhe2,D-Trp3.6]GnRH. GnRH-A stimulated phospholipase D activity after a lag of 1-2 min. We conclude that in alpha T3-1 gonadotropes GnRH receptor occupancy results in delayed activation of phospholipase D which could participate in late phases of gonadotrope regulation by the neurohormone.     

Al(3+)-mediated changes on membrane fluidity affects the activity of PI-PLC but not of PLC

We investigated whether Al(3+)-mediated changes in membrane fluidity can affect the activity of prokaryotic enzymes phospholipase C (PLC) and phospholipase C-phosphatidyl inositol specific (PI-PLC) in liposomes of phosphatidyl choline (PC), PC:phosphatidyl inositol (PI), or PC and polyphosphoinositides (PPI). Al(3+) (10-100 microM) promoted membrane rigidification, evaluated with the probes 1,6-diphenyl-1,3,5-hexatriene and Laurdan, and followed the order: PC:PPI>PC:PI>PC. Al(3+) (25 and 50 microM) did not affect PLC-mediated hydrolysis of PC, PI and PIP(2), but stimulated PIP hydrolysis (48.6%). PI-PLC did not affect PC, PI, and PIP concentrations, but caused a 67% decrease in PIP(2). Al(3+) significantly inhibited PIP(2) hydrolysis in a concentration-dependent (25-50 microM) manner. Results suggest that the inhibition of PIP(2) hydrolysis by Al(3+) could be partially due to a higher lipid packing induced by Al(3+) which could affect the interaction between the enzyme and its substrate.     

Promotion of conidia aggregation in Aspergillus niger by cyclic AMP and 5'-GMP

Cholesterol and phospholipids remain tightly associated with the ferroxidase-II protein from human serum following extensive purification. Purified ferroxidase-II preparations show a consistent ratio of protein, phospholipid, and cholesterol. Thin-layer chromatographic analyses indicate that phosphatidyl choline accounts for 70% of the bound phospholipid. Treatment of purified ferroxidase-II with phospholipase C or A results in a loss of ferroxidase activity which parallels the hydrolysis of phospholipid. A lipid-depleted form of ferroxidase-II can be prepared by gel-filtration following treatment with phospholipase C. However, hydrolysis, not removal, of the lipid is sufficient for the loss of ferroxidase activity. These studies indicate that the bound lipid components are essential to the maintainence of the catalytic activity of ferroxidase-II.     

Control of the potassium ion-stimulated adenosine triphosphatase of pig gastric microsomes: effects of lipid environment and the endogenous activator

The K⁺-stimulated ATPase activity associated with the purified gastric microsomes from the pig gastric mucosa can be completely inactivated by treatment with 15% ethanol for 60 s at 37 °C but not at 25 °C. Sequential exposure of the microsomes to 15% ethanol at 25 and 37 °C caused the release of 2.9 and 4.3% of the total membrane phospholipids, respectively, consisting entirely of phosphatidyl choline and phosphatidyl ethanolamine. The ethanol-treated (37 °C) membrane had high basal (with Mg²⁺ as the only cation in the assay mixture) activity, which was further enhanced during reconstitution with phosphatidyl choline or phosphatidyl ethanolamine. The high basal activities could be reduced to the normal control level by assaying the enzyme in presence of the “activator protein,” partially purified from the soluble supernatant of the pig gastric cells. Phosphatidyl choline was somewhat more effective than phosphatidyl ethanolamine in the restoration of the activity of the ethanol-treated enzyme while phosphatidyl serine, phosphatidyl inositol, and sphingomyelin were without any effect. Synthetic phosphatidyl choline with various fatty acid substitutions were tested for their effectiveness in the restoration of the ethanol-inactivated enzyme. The distearoyl (18:0), dioleoyl (18:1), and dilinoleoyl (18:2) derivatives of phosphatidyl choline were almost equally effective while dipalmitoyl (16:0) phosphatidyl choline was somewhat less effective in the reconstitution process. Cholesterol appeared to interfere with phosphatidyl choline in the restoration of the activity of ethanol-treated enzyme. The fatty acid composition of phosphatidyl choline and phosphatidyl ethanolamine extracted by 15% ethanol at 37 °C was clearly different than those of the total microsome. Our data suggest that the phospholipids extracted by 15% ethanol at 37 °C are derived primarily from the immediate lipid environment of the enzyme and ATP together with Mg²⁺ and K⁺ help the partially delipidated enzyme to retain the appropriate conformation for the subsequent reconstitution. Furthermore, ethanol appears to either release or inactivate the membrane-associated activator protein, demonstrated to be essential for the K⁺-stimulated activity of the pig gastric ATPase.     

Phosphatidyl inositol-specific phospholipase C from Clostridium novyi type A

From the culture broth of Clostridium novyi type A, phosphatidyl inositol-specific phospholipase C was separated from the major part of phospholipase C (γ-toxin) which hydrolyzes phosphatidyl choline, phosphatidyl ethanolamine, and sphingomyelin. Sodium deoxycholate stimulated the activity of phosphatidyl inositol phospholipase C. The concentration of sodium deoxycholate for maximal stimulation was 0.2% with 2 mm phosphatidyl inositol. Divalent cations (Mg²⁺, Ca²⁺, and Zn²⁺) were rather inhibitory above 10^?3m. Phosphatidyl inositol phospholipase C was not inhibited by EDTA or o-phenanthroline. When phosphatidyl inositol phospholipase C was incubated with rat liver slices, not only alkaline phosphatase but also 5′-nucleotidase was liberated into the soluble fraction.     

Properties of a reconstituted eukaryotic hexose/proton symporter solubilized by structurally related non-ionic detergents: specific requirement of phosphatidylcholine for permease stability

Overexpression of the hexose/proton symporter HUP1 from Chlorella kessleri in S. cerevisiae permits a one-step purification via a biotinylation domain. Milligram amounts of the protein are obtained starting from 2 l of yeast culture. The HUP1 protein is used as a model eukaryotic membrane protein of the 'major facilitator superfamily' (MFS) to study specific lipid requirements for activity and stability. Testing two series of detergents revealed that n-nonyl-beta-D-glucoside (NG) and n-octyl-beta-D-glucoside (OG) solubilize the HUP1 protein efficiently. Only the use of NG resulted in long-term stabilization of the HUP1 protein in the absence of external lipids. When affinity purified protein was extracted with organic solvents, a stoichiometric amount of phosphatidyl choline, phosphatidyl ethanolamine and ergosterol in the ratio of close to 2:1 was detected. These lipids were only observed, however, when the protein purification was carried out in the presence of NG; no lipids were copurified with the HUP1 protein in the presence of OG. Of the three lipids copurified, phosphatidyl choline showed a crucial role in ensuring maximal HUP1 permease activity and stability when added back to the OG-protein. The requirement of phosphatidylcholine documents a specific effect of lipids on vectorial transport mediated by a eukaryotic membrane protein of the MFS family.     

Radiation-induced generation and properties of lipid hydroperoxide in liposomes

The generation of hydroxyl free radicals in 60Co gamma-irradiation of a dilute aqueous suspension of phosphatidyl choline liposomes, resulted in the rapid accumulation of lipid hydroperoxides (linearly with time), but only small concentrations of malondialdehyde. Incubation of the irradiated liposomes with ferric chloride was found to significantly increase the malondialdehyde, and evidence is presented that this resulted from iron catalysed decomposition of the lipid hydroperoxide. This suggests a role for free iron or iron chelates in the propagation of lipid peroxidation stimulated by other systems.     

The effect of insulin on the permeability of phosphatidyl choline bimolecular membranes to glucose

Summary Insulin, on the outside of phosphatidyl choline bimolecular membranes, inceeased the permeability of the membranes to glucose. The magnitude of the increase in glucose permeability was dependent upon the insulin concentration and was independent of the glucose concentration over the range 2.7 to 14.4mm. The increase in the permeability of the membranes to glucose was not accompanied by a change in the direct current electrical resistance of the membranes. Ovalbumin resulted in a smaller increase in the permeability of the membranes to glucose and no change in their electrical resistance, while phloretin changed neither the permeability to glucose nor the electrical resistance. Insulin, on both sides of the bimolecular membranes, did not change the permeability to glucose from that observed when insulin was present only on the outside, nor did it change the electrical resistance.     

The utilisation of yolk phosphoglycerides by the alligator during embryonic development

Summary A study was made of the concentrations and fatty acid compositions of the major phosphoglycerides in the yolk of the alligator egg on the 8th and 75th days of incubation. The major phosphoglycerides were phosphatidyl choline and phosphatidyl ethanolamine which at the start of incubation accounted for 72 and 18%, respectively, of total phosphoglyceride. Phosphoglycerides were characterised by low levels of linoleic acid but extremely high levels of C20 and C22 polyunsaturates. The extensive absorption of phosphoglyceride over the incubation period was accompanied by a reduction in percentage of phosphoglyceride within the residual yolk lipid, a reduction in the proportion of phosphatidyl choline within the total phosphoglyceride, and increases in the proportions of phosphatidyl ethanolamine and lyso-phosphatidyl choline. There were small but wide-spread changes in the fatty acid composition of the phosphatidyl choline during incubation. Within the phosphatidyl ethanolamine and phosphatidyl serine fractions there were very large reductions in the C20 and C22 polyunsaturated fatty acid levels. The phosphoglyceride changes are discussed with respect to the unique role of yolk lipid absorption in the nutrition of the developing embryo.     

Oxidant membrane injury by the neutrophil myeloperoxidase system. II. Injury by stimulated neutrophils and protection by lipid-soluble antioxidants

The stimulated human neutrophil can damage a variety of target cells, and in some models, a mechanism involving secretion of myeloperoxidase and H2O2 has been demonstrated. We explored the characteristics of this cell-cell interaction by using neutrophils and our recently described liposome model target cell system. Exposure of 51Cr-labeled liposomes to phorbol myristate acetate-stimulated human neutrophils resulted in release of 25 to 30% of the radioactivity. 51Cr release was abrogated by omission of the neutrophils, the phorbol ester or halide (iodide), replacement of the phorbol by an inactive congener, or addition of azide, cyanide, or catalase. Neutrophils from patients with hereditary absence of myeloperoxidase (MPO) or a failure of H2O2 formation (chronic granulomatous disease) did not cause liposome lysis unless purified MPO or a source of H2O2, respectively, was added. These data indicate that 51Cr release from liposomes is a consequence of the secretion of MPO and H2O2, which combine with extracellular halides to form a membrane lytic system. The influence of liposome composition on injury was then examined, with a focus on physiologically relevant lipid soluble antioxidants. Liposomes containing either alpha-tocopherol (0.33 to 1.67% of molar fraction of lipid) or beta-carotene (1.67% of molar fraction of lipid) were markedly resistant to lysis by the cellfree MPO-H2O2-chloride system. When the major structural lipid phosphatidyl choline was replaced by dipalmitoyl phosphatidyl choline, a synthetic phospholipid with no oxidizable double bonds, the resultant liposomes were totally resistant to lysis by the MPO-H2O2-chloride system. The addition of iodide to this system (i.e., both chloride and iodide present) changed the pattern of protection dramatically in that alpha-tocopherol and beta-carotene were no longer protective and the resistance of dipalmitoyl phosphatidyl choline liposomes was partial rather than complete. In contrast to iodide, the addition of bromide or thiocyanate did not have a major effect on the protection by antioxidants. Finally, we demonstrated protection by alpha-tocopherol or dipalmitoyl phosphatidyl choline against liposome lysis by phorbol-activated neutrophils. These studies illustrate the use of model phospholipid membranes in the characterization of oxygen-dependent cell-mediated cytotoxicity. Activated neutrophils lyse liposome targets through a MPO-dependent mechanism. Target properties, especially the content of lipid-soluble antioxidants, have a marked influence on susceptibility to lysis.(ABSTRACT TRUNCATED AT 400 WORDS)     

Fluorescent probe--a cholesterol analog: localization in plasma lipoproteins and in model lipid particles

The absorption spectrum of fluorescent probe--a cholesterol analog cholesta-5,7, 9(11)-trien-3 beta-ol has a vibrational structure with the maximum 326 nm. Its fluorescence spectra maximum is 370 nm. The localization of the probe in lipoproteins of high, low and very low density and in lipid spheres is studied. There are measured the areas, which occupied one molecule of cholesterol and phosphatidyl choline on the surface of lipid spheres and the radius of the lipid spheres. The localization of the probe in lipoproteins and lipid spheres is determined. The areas which occupied one molecule of phosphatidyl choline on the surface of lipid sphere is equal to the same area in mono- and bilayers. Cholesterol has the same condensing action on phosphatidyl choline in lipid spheres as in mono- and bilayers. All the probe molecules are localized on the surface of lipid spheres and lipoproteins and the B-ring of the molecule is immersed on 1.3 +/- 0.2 nm relative to polar groups. The hydroxyl group of cholesterol is arranged near the carbonyl group of phospholipid and the formation of the H-bond between these groups is possible.