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The purpose of the research was to study seed lipids of cultivated plants: Medicago sativa, Ruta graveolens L., Linum usitatissimum L., which are growing on experimental field of I. Kutateladze Institute of Pharmacochemistry. From the above-mentioned plant seeds was obtained the sum of neutral and polar lipids, the classes were determined qualitatively. Using standard methods were determined some physico-chemical constant of oils. Fatty acids was established qualitatively and was determined quantitatively using Gas chromatography and High performance liquid chromatography methods. As a result of research in the seed oil of Medicago Sativa was revealed high percentage content of Oktadekadien - 9,12 fatty acid. Oktadekadien -9 dominates in the oil obtained from the seeds of Ruta graveolens L. and Oktadekantrien - 9,12,15 dominates in the oil obtained from the seeds of Linum usitatissimum L. Phospholipids were established qualitatively and using spectrophotometric method were determined In the sum of polar lipids: (λ 820 nm). The oils which are obtained from above-mentioned plant seeds contains biologically active compounds, which gives the opportunity to use these oils as in medical practice, also in cosmetology.

The 53 patients with chronic renocardiac syndrome, with hypertension in chronic kidney disease, were investigated. In the presence of chronic renal failure there is a decrease of cholesterol in the membrane, which is the basis for the violation liquid characteristics of cell membranes. Changes in the exchange of phospholipids and an increase in the exchange rate reflect increasing phosphatidylcholine lipid peroxidation, increasing in chronic renal failure. The degradation of cell membranes reflects a compensatory accumulation in these fractions of phosphatidylcholine, a major component of the outer layer of biomembranes. Regardless of the degree of renal dysfunction and clinical manifestations of the disease in the membranes of platelets accumulate lizoform phospholipids, indicating a strengthening of the processes of lipid peroxidation and accumulation of biologically active substances, which have membrane-destructive activity.

The effect of an extract from tunic of the sea hydrobiont purple ascidium (Halocynthia aurantium) on the lipid metabolism in the liver of mice has been studied under the acute stress conditions modeled by fixing animals for 22 h at the dorsal neck fold. The extract from purple ascidium tunic is superior to essentiale (well-known commercial hepatoprotector) in the efficacy of restoring lipid fraction content (tryglycerides, cholesterol, free fat acids, lysophospholipids) disturbed by stress action. In addition, the extract normalizes the esterification function of the liver. The observed effect of the purple ascidium tunica extract is related to a combined action of the "marine" phospholipids that are present in the preparation and are known to possess reparative properties.

Hydrolysis of lipids from beef fat by pancreatic lipase was studied. Maximal release of free fatty acids was shown to take place for the first 3 h of experiment. After this, transetherification developed. Following most important time course parameters were determined: maximal hydrolysis rate V = 1.25 +/- 0.1 mg fat/(ml min), Michaelis constant KMH = 100 +/- 12 mg fat/ml, constant of substrate inhibition KS = 10.0 +/- 0.8 mg fat/ml, equilibrium constant KP = 277 +/- 170 mg fat/ml, and activation energy of beef fat hydrolysis by pancreatic lipase Ea = 19.1 +/- 1.1 kJ/mole. The time course method used could be applied to develop biotransformation of poorly assimilated fats to more valuable products.

The paper describes the composition of extracellular free fatty acids (FFAs) and intracellular fatty acids (FAs) in the enrichment cultures of the prokaryotic alga Spirulina platensis and the eukaryotic alga Chlorella vulgaris grown at optimal, supraoptimal, and suboptimal growth temperatures. With increasing growth temperature, the degree of unsaturation of the intracellular FAs of both algae decreased, while that of the extracellular FFAs of S. platensis increased. The composition of the extracellular FFAs of C. vulgaris practically did not depend on the growth temperature.

Unidimensional chromatography in a thin layer of silica gel with two solvent systems for separation of the lipid extract of high density lipoproteins (HDLP) detected 10 lipid fractions in subjects with normal lipidemia. Four phospholipid fractions were identified: three main (phosphatidylcholine, lysophosphatidylcholine, and sphingomyelin) and one minor, phosphatidylethanolamine. HDLP lipids include free cholesterol and its esters; three glyceride fractions are detected: mono- di, and triglycerides, and free fatty acids. The ratio of individual phospholipid fractions and of free to ester-bound cholesterol in HDLP determined by computer-aided densitometry of chromatograms coincides with the data obtained routinely. Such a method for assessing the HDLP lipid composition is useful in studies of HDLP in patients with disorders of HDLP metabolism and for assessing the changes in HDLP composition during hypolipidemic therapy.

The influence of isolation procedures on physico-chemical properties of human serum albumin (HSA) has been studied using differential scanning calorimetry and infrared spectroscopy. Fractionation of blood plasma with polyethylene glycol (PEG) followed by ion-exchange chromatography produced healthy donor albumin whose melting thermograms were identical to those of the HSA in non-fractionated plasma. The endotherms of HSA samples isolated by affinity chromatography (AC) and native electrophoresis (EP) are bimodal as distinct from monophasic endotherms of PEG-HSA preparations. The changes in the melting curves result from increased levels of nonesterified fatty acids in AC-HSA samples and modification of the protein secondary structure revealed in EP-HSA samples by IR-spectroscopy. Analysis of HSA melting thermograms in patients with uremia, chronic hepatitis and peritonitis revealed that the PEG method permits to preserve, in the greatest degree, the thermodynamic features of various "pathological" HSA. The experimental results demonstrate the advantage of the PEG technique in isolation of native HSA in the norm and under pathology.

Changes in the blood levels of glucose, lactate and free fatty acids, and glycogen in the livers and skeletal muscles of rats (n = 47) on epinephrine administration (150 mcg/kg body weight) were studied on Day 7 of a recovery period following hypokinesia of 15 and 30-day durations. In the animals exposed to restrained motor activity, as compared to normal rats, epinephrine has a less effect on glycogen content in the muscle, is not accompanied by increased serum levels of free fatty acids and results in more marked elevation of blood lactic acid levels. Adrenal control of lipolytic processes in the adipose tissue and of glycogenolytic processes in the muscles in the post-hypokinetic recovery period is reduced.

A study was made of the content of cAMP, triglycerides and nonesterified fatty acids in the liver of rats anesthesized with halothane under conditions of spontaneous respiration depending on the oxygen content in the inhalation mixture. As the content of oxygen in the inhalation mixture was reduced, the content of cAMP in the liver was decreased, the intensity of lipolysis was disturbed with subsequent derangement of fatty acids oxidation. The raising of the oxygen content in the inhalation mixture did not disturb the activity of the adenylate cyclase system or provoked deep lipolysis disorders in the liver.

The influence of continuous gamma irradiation on the lipids of nuclei and chromatin of rat liver at a dose-rate of 0,129 Gy/day for 155 days (a total dose of 20 Gy) and by feeding of ubiquinone-9 has been studied. The amount of phosphatidylcholine with phosphatidylserine and phosphatidyl-ethanolamine in liver nuclei of irradiated rats was found to increase. Ubiquinone-9 had a normalizing effect. A decrease of cardiolipin was observed in the liver chromatin of irradiated rats. The amount of free fatty acids had a tendency to decrease in homogenate, nuclei and liver chromatin of irradiated rats. Ubiquinone was found to increase the amount of free fatty acids up to the control level. The amount of cholesterol in nuclei was increased after irradiation and that in chromatin tended to rise. Ubiquinone-9 significantly decreased the amount of cholesterol in nuclei and chromatin of irradiated rats.

Twenty-one patients suffering from paroxysmal tachycardia (PT) were examined for metabolism of nonesterified fatty acids (NEFA) in the myocardium as well as for interrelations with the parameters of clinical electrophysiology. It has been shown that the main features of NEFA metabolism in the myocardium of RT patients lie in their high concentration in arterial blood and in the blood of the coronary heart sinus and in their high ratio of extraction by the myocardium both in the presence of sinus rhythm and during RT, which is of the pathogenetic importance in the origin of heart rhythm disturbances. NEFA exert different effects on the antegrade and retrograde (functional and effective) refractory periods of different parts of the conduction system of the heart, favouring the onset of their electrophysiological heterogeneity.

Experiments on rats with chronic bipolar electrodes implanted into the frontal cortex (FC), dorsal hippocampus (DH) and midbrain reticular formation (RF) established that the neurotic state (model "conflict of afferent excitation") was characterised by the increase in structure excitability: FC--15.4% (P less than 0.01), DH--12.4% (P = 0.05) and RF--17.5% (P less than 0.001). The presence of free fatty acids (FFA) revealed by chromatograph Schimadzu in brain cortex (BC), hippocampus (H) and midbrain (MB) in acute experiments evidenced the increase in the level of linolinic acid in all matters within the limits of 64-162% (P less than 0.05) and also different changes in arachidonic acid in BC and subcortical structures. The level of arachidonic acid increased by 120% (P less than 0.01) in BC but it decreased in H and MB within the limits of 34-56%. AVP (1 micrograms/kg) decreased excitability of FC by 6% (P less than 0.001), of H--by 8% (P less than 0.01) and RF--by 6%. In this case FFA, especially arachidonic acid, was increased in H and MB (by 2.5-6 times). The quantity of palmitic, stearic and oleic acids increased.

The composition of free fatty acids of lipids in different rat brain structures (the cortex, hippocampus, striatum and midbrain) in neurosis was studied by the gas chromatographic analysis. The difference in their spectra was established. A pronounced increase of arachidonic acid content in the cortex (by 120%, p less than 0.01) and a statistically significant elevation of linolic acid level in all studied structures were noted. The levels of pentadecanoic and myristic acids were also changed. In neurosis diazepam (0.5 mg/kg, intraperitoneally, 40 minutes before the investigation) produced a decrease in the brain cortex of levels of arachidonic, oleic and myristic acids. In the hippocampus the contents of oleic and myristic acids increased. Less pronounced changes were found in the striatum and midbrain.

The physico-chemical properties of preparation MIGI-K from mussels are given. Some characteristics of melanoidin fractions of MIGI-K are presented, their similarity to standard melanoidin is revealed. The given data on biological activity of the preparation permit to consider MIGI-K as immunomodulator.

It was experimentally established that a single administration of hydrocortisone to rabbits in a dose of 50 mg/kg caused a reduction in the lymphoid cells of the mesenteric lymph nodes of triglycerides and free fatty acids; this was accompanied by a fall of total lipids in the cells.

Quantitative estimation of free fatty acids was carried out in liver mitochondria of normal and thyroidectomized rabbits by means of two procedures--spectrophotometry using rhodamine 6Zh and a fluorescent method with 1,8-aniline naphthalene sulfonate /ANS/ as a dye. The use of ANS enabled to estimate quantitatively the free fatty acids beginning from 25 nmol in a sample /with eggor of about 17%/ by visual evaluation of the spot areas. As compared with the rhodamine procedure, use of ANS permitted to increase 5-fold the sensitivity of free fatty acid estimation, to elevate 6-fold the accuracy of the analysis, to overcome the step of fatty acid elution from chromatogramms and to decrease the time required for analysis. The data obtained suggest that the hyperthyroid state in rabbits was accompanied by an increase in the phospholipase A2 activity in liver mitochondria.

Composition of nonesterified fatty acids/NEFAj from Shigella Flexneri was similar to that from other Gram-negative bacteria of the enteritic group. At the same time, NEFA of the dysenteric bacteria contained comparatively high amount of branched and cyclopropane-bearing fatty acids. Adaptation of Shigella Flexneri in the medium of developing chicken embryo led to a distinct increase in total NEFA content as well as of cyclopropane-bearing and saturated fatty acids in the bacteria and to a decrease in content of branched-chain and unsaturated fatty acids. Total content of NEFA and of unsaturated fatty acids was increased, but their qualitative composition became poor in amnions of developing chicken embryons under conditions of their infection with the Shigella.

Alterations in lipid composition of rat adrenal glands were studied at various periods of autolysis by means of micro-thin layer chromatography. Phospholipids, cholesterol and its esters proved to be the most labile lipid fractions of the tissue. At early period of autolysis (4 hrs) content of total lipids was decreased mainly due to lowering in amount of phospholipids, cholesterol and its esters and only slightly - to lowering in content of free fatty acids. In subsequent necrobiotic degradation of adrenal gland tissue (10 hrs) the increase in content of total lipids was related to the distinct elevation in amount of free fatty acids and glycerides. Mechanisms of the phenomenon observed are discussed.

In a series of 62 patients with variable forms of epileptic attacks the electrochemiluminescent (ECL) parameters of free radical oxidation (FRO) and antioxidant activity (AOA), the content of malonic dialdehyde (MDA) and free fatty acids (FFA) in the blood and cerebrospinal fluid (CSF) were collated with clinico-electroencephalographic characteristics of the disease. The CSF of all patients showed intensified FRO and inhibited AOA which significantly prevailed in cases of uncontrolled paroxysms; for all cases a progressive course of the disease with the development of encephalopathy and psychopathologic syndromes was characteristic, as well as generalized and frequent attacks, the presence of extraparoxysmal epileptic patterns on the ECG and the postparoxysmal syndrome. The spectrum of FRO and AOA parameters in patients with "forced normalization" and signs of drug poisoning are similar to quantitative characteristics of FRO and AOA in cases of frequent attacks and EEG characteristics of the paroxysmal type. The results of the study allow the conclusion that FRO and the electrochemical substrate of epileptization are two parallel closely related processes.

Activities of glucose-6-phosphate dehydrogenase (G6PD), lactate dehydrogenase (LDH) as well as lipolytic activity were decreased in lymphoid cells of lymphatic glands from rabbit mesentery as compared with corresponding levels of the enzymatic activity in cells of bone marrow. The isozyme spectra of G6PD, LDH and unspecific esterases were dissimilar in lymphoid and bone marrow cells. Content of total lipids, triglycerides, free fatty acids as well as the hexokinase and lipolytic activities were decreased in the cells after treatment with hydrocortisone.

Examination of 43 patients with various forms of epilepsy has shown that the plasma levels of lipid peroxidation (LPO) products and free fatty acids (FFA) are two to fivefold higher as against those in healthy donors. The concentration of LPO products in the cerebrospinal fluid of epileptic patients is 4-5 times higher, whereas FFA levels are 10 times higher than the corresponding levels in the blood plasma. The plasma content of LPO products and FFA are mostly influenced by age, the disease duration, the presence of generalized convulsive paroxysms and the degree of personality changes. The plasma levels of LPO products have been found to correlate with FFA levels (r = 0.63; r = 0.28). A conclusion is drawn that the changes detected in the plasma concentration of LPO products and FFA reflect alterations in the activity of the LPO process in the CNS of epileptics. It is suggested that the determination of FFA levels may be used for monitoring the LPO in epileptic patients.

UV spectrophotometry and high-resolution NMR spectrometry have demonstrated the formation of the complexes of ionol and fatty acids. This formation occurs as a result of the two types of interactions: 1/hydrogen bond formation between ionol OH-group and the carboxylic group of a fatty acid; 2/van der Waals interactions between the hydrogen chain of a fatty acid and tret -butyl groups of ionol. The latter interaction becomes more powerful with increase in fatty acid unsaturation. The molecular structure of the complexes of ionol with fatty acids is suggested.

Total content of unesterified fatty acids and activity of ATPases/latent, stimulated by Mg2+, 2,4-DNP, Mg2+ and 2,4-DNP/were studied in heart and liver mitochondria of rabbits with decompensated mitral valvular disease. The activities of Mg2+, DNP-, Mg2+ and DNP-stimulated ATPases were decreased in heart mitochondria. At the same time, content of unesterified fatty acids was increased. Content of the fatty acids was decreased in liver mitochondria and activity of ATPase was unaltered. Possible mechanisms of the alterations observed are discussed.

An improved modification of the Anderson-Chakrabarty method for demonstration of free fatty acids in the membranes of enterocytes, erythrocytes and mitochondrial fractions is described. The method includes the use of rhodamine 6G as a stain.

By thin-layer chromatography on silica gel L (Czechoslovakia) monoglycerides, diglycerides, free fatty acids and triglycerides were isolated from free lipids of ripeining wheat. The composition of free fatty acids of these fractions was studied by gas-liquid chromatography. The following fatty acids were identified and quantified: C10:0; C12:0; 14:0; C14:1; X15:0; C16:0; C17:0; C18:1; C18:2; C18:3; C20:09 Linoleic, palmitnic, oleic, stearic and linolenic acids accured in large quantities. The wheat ripeinig was followed by a decrease in the sum total of saturated and an increase of the sum total of unsaturated fatty acids. During ripening the content of biologically important linoleic acid increased: in monoglycerides from 42.6 to 19.5%, diglycerides from 51.0 to 62.4%, in free fatty acids from 48.8 to 51.0% and in triglycerides from 54.5 to 61.1%, whereas the content of palmitinic and linolenic acids diminished.

Comparative study of content of main lipid fractions was carried out in five parts of rabbit myocardium by means of thin-layer chromatography on silicagel with subsequent quantitative estimation. Increased concentrations of free and esterified cholesterol, free fatty acids and triglycerides were observed in atrium dextrum and triglycerides in ventriculus dexter as compared with either the corresponding left-side parts of the heart muscle or with septum interventriculare. Content of cholesterol esters, free fatty acids and triglycerides was higher in atrium dextrum as compared with ventriculus dexter. The lowest concentration of phospholipids was approximately the same in other parts of the heart muscle.

Experiments were conducted on rats; the gas chromatographic method was applied to the study of the free fatty acids content in the gastrocnemius 30 minutes after the intraperitoneal injection of adrenocorticotropic hormone (ACTH)--1 Unit per 100 g and hydrocortisone acetate--1 mg per 100 gm of body weight. It was shown that in the resting muscles ACTH increased the content of stearic acid, whereas hydrocortisone--of both stearic oleic acids. The changes in the content of other free fatty acids were insignificant. During the short-term activity the content of stearic acid in the regimen of single rhythmic contractions in the gastrocnemius of intact rats increased. In experiments with ACTH and hydrocortisone this elevation was much less and not significant. ACTH and hydrocortisone stimulated the stearic acid consumption by the muscles during the activity.

The kinetics of the free fatty acids accumulation in membranes of isolated mitochondria of the brain, heart and liver of rats, with their incubation in a medium containing no substrates and ATP, was studied. The intensity of the phospholipase damage, measured by the rate of free fatty acids accumulation, augments in the sequence of: the liver-heart-brain. The amassment of fatty acids in the mitochondrial membranes is shown to give place to their penetration into the inner space of the mitochondria. A relationship between the content of the intramitochondrial calcium and the concentration of free fatty acids in in the membranes, on the one hand, and the degree of passive swelling of the cardiac mitochondria, on the other, was revealed. It is suggested that the free fatty acids or their derivatives act as carriers of calcium to the mitochondrial membrane. A preliminary administration to rats of the vitamin E and sodium selenite protects the mitochondria of the heart against the phospholipase damage. These agents display a synergic action and are effective with administration of physiological doses. It is presumed that the protective action of these substances is due to the stabilization of biological membranes.

After administration of insulin into rats activity of dehydrogenases of pentosephosphate pathway was not altered in cortex and medulla of kidney as distinct from the liver tissue. Concentration of free fatty acids was slightly lower in soluble fraction of kidney cortex than in blood plasma and higher than in preparation from kidney medulla. Alterations in content of free fatty acids were not observed in the preparations of kidney of rats with alloxan diabetes.

The ability to oxidize n-alkanes was studied with various species of fungi belonging to the Cunninghamella genus. These fungi are able to assimilate hydrocarbons and to accumulate up to 1.5 g/litre of biomass. The most active strain was Cunninghamella elegans (-) 1204. The amount of lipids formed, and their composition, depended on the length of the carbon chain of oxidized alkane. The content of fat in the cells increased with the length of the hydrocarbon chain. The following lipid fractions have been detected: phospholipids, monoglycerides, diglycerides, triglycerides, sterols, free fatty acids, sterol esters, and hydrocarbons. The qualitative composition of the fractions depended, to a considerable extent, on the n-alkane utilized. Investigation of the fatty-acid composition of intracellular lipids has shown that fatty acids with an even number of carbon atoms are formed from hydrocarbons with an even number of these atoms, while fatty acids both with an even and odd number of carbon atoms are synthesized from hydrocarbons with an odd number of these atoms. The relative content of the acids with the same number of carbon atoms as that of the alkane being utilized increased with the length of the carbon chain.

During preparation to hibernation in E. arguta, fat stores increase together with glycogen content of the liver and partially of the muslces. Due to the decrease in locomotor activity of the animals, the level of unsaturated fatty acids in muscles increases. During 1- and 3-week hibernation (body temperature 2-4 degrees), glycogen of the liver and muscles is utilized. During 5-week hibernation, glycogen content of the liver and muscles increases as compared to 3-week hibernation by 3.5 and 2.3 times. In the brain the level of glycogen at all stages of hibernation is 1.4--2.1 times higher than in control animals. No accumulation in tissue lactate was observed during hibernation.

Gas-liquid chromatogrophy was used to study the skin and sebum cutaneum of 6 male test subjects (aged 45-55) before and after 30-day enclosure. The greatest changes were seen in the composition of free fatty acids of lipids of the facial skin (increase of palmito-oleic acid). The lipid composition of the sebum cutaneum of the healthy subjects differed from that of the acne-bearing subjects. It is recommended to use the ratio of palmitic acid to palmito-oleic acid as a measure of changes of fatty acids in the sebum cutaneum of healthy people in an unusual environment.

Consequent upon the results of investigating fatty acids composition in the tissue lipids of a number of marine fish (marmoreal and green nototenia, merow, stavrida, klykach, lufar, marine perch and marine bream) of different degrees of fatness there were ascertained substantial differences in the correlation of basic acid components and the nutritional value of the lipids. A comparison between the overall lipid content and the quantity of highly unsaturated acids enabled it to disclose a possible relative resistance of the studied fish to the oxidative lipids decay.

A new modification of a highly sensitive horizontal flow chromatography procedure for the study of lipid composition of intracellular membranes is proposed. This modification employs application of thin layers of homogeneous silicagel particles by precipitation from diluted water suspensions in a cell of original construction, which allows to obtain by a single analysis distinct lipid fractions having similar chromatographic mobility. Using this modification, the major forms of lysophosphatides, i. e. lysophosphatidylcholines, lysophosphatidylethanolamines, lysocardiolipids, lysophosphatidic acids, lysophosphatidylserines, etc., and their diacyl analogs were isolated from mitochondrial and reticulum membranes and identified. The contents of mono-, di- and triglycerides, free fatty acids, cholesterol and its esters were determined.

Total cellular lipids of the synthetic of vitamin B12 Act. olivaceus involve predominantly phospholipids (about 70%). Lipid phosphates consist of phosphatidyl ethanol amine and phosphatidyl-2,3-butandiol (over 40 and 30%, respectively) and lower quantities of phosphatidyl inositol olmonomanoside and cardiolipin. The neutral fraction includes the predominating fraction of triglycerides (over 20%) as well as mono- and diglycerides, free fatty acids, hydrocarbons and three fractions similar to waxes, sterines and sterine esters in their Rf values.

Endotracheal phthorothan anesthesia without any surgical intervention in rabbits for 3.5 hours diminished the surface active properties of the surfactant by increasing the surface tension of the lung washings measured on the Wilhelmy scales. A study of phospholipid fractions in the lung washings by means of the thin-layer chromatography on silicagel showed a decrease of one of the major structures of the surfactant lipoprotein, phosphatidylcholine, with a simultaneous increase of the lysophosphatidylcholine. Determination of the free fatty acid content in the lung washings after the action of phthorothan anesthesia showed their significant increase as compared with control. A possible mechanism of the damaging effect of phthorothan anesthesia on the lung surfactant is discussed.

A week hypothermia (2-4 degrees C) does not cause a considerable decrease in content of glycogen in the liver, muscles, brain tissues of Lacerta strigata, Natrix tessellata and Rana ridibunda. In Eremias arguta pangolins the level of glycogen in the liver and muscles under these conditions is twice as low. Prolongation of hypothermia till three weeks causes a 4-fold decrease in the polysaccharide level in the liver of Eremias arguta and Lacerta strigata. The content of nonesterified fatty acids in blood under hypothermia (especially of three-week one) considerably exceeds the normal level. The content of lactic acid in tissues is two-three times as high under prolonged hypothermia, in the reptile muscles creatine phosphate accumulates in high amounts.

Peculiarities of the hormonal regulation of physiological functions have been studied in intact and adrenalectomized albino rats with respect to the seasons. Glucocorticoids have been shown to determine, to a large extent, the activity of parameters of the immune system in spring, whereas in autumn their regulatory effect is most pronounced with relation to the indices of energetic homeostasis.

Mitochondria obtained from hyperthyroid rabbit liver contained an approximately 4-fold greater amount of free fatty acids (FFA) than preparations from the control animals. The temperature dependence of FFA accumulation (29--38 degrees C) showed that the activation energy of mitochondrial lipid hydrolysis for control and experimental animals was 7 kcal/mole and 29 kcal/mole, respectively. The mitochondria were kept at 3 degrees C for 48 h. During this period there was an accumulation of fatty acids. The rate of the process in the mitochondria of hyperthyroid animals was several times than that in the control ones. This indicates the activation of mitochondrial phospholipase by the liver in hyperthyrosis. The increased mitochondrial phospholipase activity seen in hyperthyrosis is assumed to be determined by changes in the physical properties of lipid membranes.