[Effects of hydrocortisone and insulin on the electrokinetic potential of hepatocyte nuclei]. / Elektrokineticheskii potentsial iader gepatotsitov pri vozdeistvii gidrokortizona i insulina.

The electrokinetic potential of liver cell nuclei of rats after the in vivo separate and joint injection of hydrocortisone and insulin was determined. It was shown that the steroid induces a significant elevation of the value of electrokinetic potential while insulin does not change this parameter. An insignificant elevation of the potential by the joint action of the hormones was found, which apparently is indicative of the antagonism between hydrocortisone and insulin.

[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 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.