Age-associated changes of rat brain neuronal and astroglial poly(ADP-ribose) polymerase activity.
Nuclear poly(ADP-ribose) polymerase levels as well as the DNA strand break levels of whole-brain neuronal and astroglial cells were investigated. Three- and 30-month-old rats were used. Low-molecular-weight neurofilaments and glutamine synthetase served as neuronal and astroglial markers, respectively. A large increase in the poly(ADP-ribose) polymerase activity was observed in the neurons (threefold) and astrocytes (3.7-fold) derived from 30-month-old rats. Similarly, the amount of poly(ADP-ribose) polymerase, evaluated per milligram of DNA, increased approximately 3.5-fold in neurons and 3.9-fold in astrocytes prepared from 30-month-old rats. Whether the increase in the poly(ADP-ribose) polymerase activity was due to an enhanced rate of DNA strand break was investigated by determining the rate of DNA unwinding. A significant increase in DNA unwinding rate was detected in the neurons (2.7-fold), although a lower increase was observed in the astroglia (1.3-fold) of aged animals.
Messripour
M
M
Department of Biochemistry, Isfahan Medical Sciences University, Iran.
Weltin
D
D
Rastegar
A
A
Ciesielski
L
L
Kopp
P
P
Chabert
M
M
Mandel
P
P
D000375:Aging / Q000502:physiology*; D000818:Animals; D001253:Astrocytes / Q000201:enzymology*; D001921:Brain / Q000166:cytology / Q000201:enzymology*; D004247:DNA; D009474:Neurons / Q000201:enzymology*; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
D004247:DNA; D011065:Poly(ADP-ribose) Polymerases