[Shifts in phospholipid composition of the nuclear matrix in rat liver cells exposed to insulin]. / Sdvigi v sostave fosfolipidov iadernogo matriksa kletok pecheni krys pri vozdeistvii insulina.

It was shown that the total content of phospholipids of rat liver nuclear matrix increased after in vivo action of insulin (2 units per 100 g of animal weight). At the same time the sphyngomyelin content was increased and the content of phosphatydilcholine and phoshpatydilinositol was decreased significantly under the hormone action. The decreasing of monophosphoinositides amount was accompanied by the increasing of triphosphoinositides content which indicates the redistribution among the phosphoinositides fractions under the hormone action and may be the result of insulin initiation of phosphoinositide pathway in nuclear membrances.

[Effect of insulin on the composition of chromatin phospholipid in rat liver cells]. / Deistvie insulina na sostav fosfolipidov khromatina kletok pecheni krys.

In vivo the action of insulin on rat liver chromatin phospholipid composition was investigated. It was shown that the hormone led to reliable increase (nearly 20%) of total phospholipid content. The same phenomenon was shown also in the fraction of active chromatin while the phospholipids content of non-active chromatin didn't changed. It was also shown that the content of three from six phospholipid fractions altered under the insulin action. The content of sphingomyelin and phosphatidilethanolamine increased and the quantity of phosphatidylinositol decreased under the hormone action. The decrease of monophosphoinositides content was accompanied by the reliable increase of triphosphoinositides amount. It was suggested that the fractions of chromatin polyphosphoinositides were redistributed under the action of insulin.

[Effect of hydrocortisone on composition of polyphosphoinositides in liver cell nuclear membrane and rat brain]. / Deistvie gidrokortizona na sostav polifosfoinozitidov iadernykh membran kletok pecheni i golovnogo mozga krys.

The action of hydrocortisone in vivo was shown to cause changes both in the total amount of phospholipids and polyphosphoinositides of rat liver and brain nuclear membranes. The hormone increased the content of five from seven phospholipid fractions including the fraction of monophosphoinositide when acting in concentration and exposition leading to activation of biosynthetic processes. The increasing of monophosphoinositides amount was accompanied by the decreasing of triphosphoinositides content which indicated the redistribution among the phosphoinositides fractions under the steroid hormone action in both cell types.

[Effect of estradiol on phosphoinositide composition of nuclear membranes of rat brain cells]. / Deistvie éstradiola na sostav fosfoinozitidov iadernykh membran kletok golovnogo mozga krys.

The effect of estradiol on phospholipids and particularly on phosphoinositides of nuclear membranes of rat brain cells at different stages of hormone action was investigated. It was shown that hormone leads to the elevation of phospholipids total amount at the primary and early stages of its action (1 and 4 h after estradiol injection, correspondingly). The increase of content of almost all individual fractions of phospholipids as well as phosphatidylinositol (i.e. monophosphoinositide) was detected. It is remarkable that the monophosphoinositides elevation takes place mainly due to the decrease of di- and especially of triphosphoinositide. The ratio of triphosphoinositide/monophosphoinositide decreases more than twice. It was concluded that the ratio of triphosphoinositide to monophosphoinositide may be a peculiar indicator of the status of nuclear membranes for the functioning of triphosphoinositide regulatory system.

[An increase of CDP-choline: diglyceride phosphocholine transferase reaction in microsome fraction and its decrease in nuclear membranes of the rat liver after treatment with hydrocortisone]. / Povyshenie CDP-kholin: diglitseridfosfokholintransferaznoi aktivnosti fo fraktsii mikrosom i snizhenie--v iadernykh membranakh pecheni krys pri vozdeistvii gidrokortizona.

The availability of CDP-choline: diaglyceride phosphocholine transpherase activity in the rat liver nuclear membrane fraction is shown. It is established that the enzyme activity in nuclear membrane fraction makes up less than 1/3 of the analogous activity in microsomes. The hydrocortisone treatment of animals leads to an increase of the enzyme activity in microsomes and to a decrease in the nuclear membranes. The obtained data indicate the existence of the own enzyme of phosphatidyl choline synthesis in the nuclear membranes. This enzyme is, probably, responsible for the nuclear membrane structure when the functional status of cell changes.

[Action of hydrocortisone on the lipid composition of active and inactive chromatin fractions in the rat liver]. / Deistvie gidrokortizona na lipidnyi sostav aktivnoi i neaktivnoi fraktsii khromatina pecheni krys.

A composition of phospholipids and neutral lipids of rat liver chromatin and its active and inactive fractions has been investigated. It is shown that the hydrocortisone action results in marked increase in phospholipid/neutral lipid ratio of both chromatin and its active fraction. The changes in lipid content is clearly expressed in active chromatin fraction, the lipid content of inactive fraction is not changed. It is concluded that the increase of content in certain phospholipids and simultaneous decrease of neutral lipids in chromatin promotes the hormonal activation of genome.

[Neutral lipids of nuclear membranes and chromatin in rat liver after hydrocortisone administration]. / Neitral'nye lipidy iadernykh membran i khromatina pecheni krys pri vozdeistvii gidrokortizona.

It is shown that over 80% of nuclear neutral lipids are found in the nuclear membrane preparations, whereas only 7%--in chromatin. The injection of hydrocortisone to animals significantly decreases the neutral lipids content in both fractions. These results and the data obtained previously by the authors indicate the possible participation of nuclear membrane and chromatin lipids in the process of hormonal regulation of the genetic activity.

[Lipid composition of the rat liver nuclear matrix as affected by hydrocortisone]. / Lipidnyi sostav iadernogo matriksa pecheni krys pri vozdeistvii gidrokortizona.

It has been found that the rat liver nuclear matrix contains a small amount of phospholipids (2%) and neutral lipids (1.6%). The injection of hydrocortisone increased the nuclear matrix phospholipid content and reduced its neutral lipid levels. A marked increase in sphingomyelin content observed was accompanied by the reduction in phosphatidylcholine level. The decrease in neutral lipid content took place mainly at the expense of a sharp lowering of triglyceride and cholesterol ether levels. The latter may turn into free cholesterol, thus increasing its content. The data obtained testify to steroid hormone influence on lipid metabolism in intranuclear structures. The observed changes in lipid composition may be related to specific hydrocortisone-induced activation of genome.

[Effect of hydrocortisone on the phospholipid composition and activity of various enzymes of phospholipid metabolism in the nuclear membranes of the rat liver]. / Deistvie gidrokortizona na fosfolipidnyi sostav i aktivnost' nekotorykh fermentov metabolizma fosfolipidov v iadernykh membranakh pecheni krys.

It was shown that hydrocortisone injections markedly increase the total content of liver nuclear membrane phospholipids, the greatest increase being observed in the phosphatidyl choline level. It was found also that nuclear membranes contain phospholipid metabolism enzymes. The hormone-induced increase in the phospholipid content is accompanied by a marked decrease of the activity of phospholipase A2 (5.3 times against control), phospholipase C (9.3 times) and acyl-CoA: lysophosphatidylcholine transferase (2.5 times). The results obtained are suggestive of appreciable metabolic changes in nuclear membrane phospholipids caused by hydrocortisone which, in turn, may be due to hormonal activation of the genome.

[Changes in the phospholipid composition of rat liver chromatin during treatment with hydrocortisone]. / Izmenenie sostava fosfolipidov khromatina pecheni krys pri vozdeistvii gidrokortizona.

When isolating protein components of chromatin from the rat liver phospholipids are found in the fraction of nonhistone proteins but not in that of histone. Administration of hydrocortisone to animals evokes a reliable increase of the phospholipids of hydrocortisone to animals evokes a reliable increase of the phospholipids amount in the preparations of chromatin and labile-bound nonhistone proteins. In this case the fraction of phosphatidylcholine lowers considerably with a simultaneous increase of sphingomyelin and phosphatidylethanolamine. It is supposed that phospholipid metabolism in chromatin is controlled by hormones, which may be significant for mechanisms of the genetic apparatus activation by steroid hormones.