[The effect of Cu2+, Zn2+ cations and biogenic amines on the nuclear poly(ADP-ribose) polymerase activity in the rat brain]. / Vliianie kationov Cu2+, Zn2+ i biogennykh poliaminov na iadernuiu poli(ADP-riboza) polimeraznuiu aktivnost' golovnogo mozga krys.

Study of the effects of Cu2+, Zn2+ cations and polyamines, spermine and spermidine, on the nuclear poly(ADP-ribose)polymerase activity of rat brain was carried out. It was shown that low concentrations of Cu2+ stimulate the activity of purified poly(ADP-ribose)polymerase. The poly(ADP-ribose)polymerase activity was increased 1.4-fold at 5 microM Cu2+. A further increase of Cu2+ concentration inhibited the enzymatic activity; at 50 microM Cu2+ the polymerase activity appeared to be fully inhibited. It was shown that Zn2+ inhibited only the poly(ADP-ribose)polymerase activity. Zn2+ at a concentration of 125 microM fully inhibited the enzymatic activity. Spermine and spermidine stimulated the poly(ADP-ribose)polymerase activity of brain nuclei of newborn and old rats.

[The effect of the x-ray irradiation of rats on the NAD-pyrophosphorylase and poly(ADP-ribose)polymerase activities of brain nuclei and on the NAD content in nerve tissue]. / Vliianie rentgenovskogo oblucheniia krys na NAD-pirofosforilaznuiu i poli(ADP-riboza)polimeraznuiu aktivnost' iader golovnogo mozga i na soderzhanie NAD v nervnoi tkani.

A study was made of the influence of X-irradiation of rats with various doses on NAD-pyrophosphorylase and poly(ADP-ribose) polymerase activity of brain nuclei. It was shown that X-radiation was ineffective with regard to NAD-pyrophosphorylase activity of nuclei and increased their poly(ADP-ribose) polymerase activity. Stimulation of poly(ADP-ribose) polymerase activity of nuclei was a function of radiation dose and correlated with the decrease in the NAD content of nervous tissue. It was found that mainly nonhistone proteins were ADP-ribosylated in nuclei of both irradiated and nonirradiated rats.

[Study of nuclear poly(ADP-ribose)polymerase and DNA-topoisomerase II of brain cells during postnatal development of rats]. / Izuchenie poli(ADP-riboza)polimerazy i DNK-topoizomerazy II iader kletok golovnogo mozga v period postnatal'nogo razvitiia krys.

The nuclear poly(ADP-ribose)polymerase activity of neuronal and glial cells during postnatal development of rats was studied. It was shown that the poly(ADP-ribose)polymerase activity of nuclei and nuclear matrix of neuronal cells during postnatal development of rats is increased, whereas the polymerase activity of glial cell nuclei and nuclear matrix in newborn and adult rats is higher than in 14-day-old animals. The DNA-topoisomerase II activity of neuronal nuclear matrix during the postnatal development of rats does not change, whereas the topoisomerase activity of glial nuclear matrix decreases but is always higher than the DNA-topoisomerase II activity of neuronal cell matrix during the postnatal development of rats. It is suggested that ADP-ribosylation in the nuclear matrix of neuronal cells causes the inhibition of the DNA-topoisomerase II activity of nuclear matrix.

[ADP-ribosylation of nuclear proteins in the rat brain]. / ADP-ribozilirovanie iadernykh belkov golovnogo mozga krys.

The distribution of (ADP-ribose)n synthesized from [14C]NAD labeled at the adenyl ring in several protein fractions of isolated rat brain nuclei was studied. Preferential ADP-ribosylation of nonhistone nuclear proteins was shown to occur. It was demonstrated that pol (ADP-ribose)polymerase and DNA-topoisomerase II are located spatially close to each other. A correlation between ADP-ribosylation and the activity of nuclear matrix DNA-topoisomerase II was established.