Age-Associated Changes of Rat Brain Neuronal and Astroglial Poly(Adp-Ribose) Polymerase Activity Pubmed



Messripour M¹ ; Weltin D² ; Rastegar A² ; Ciesielski L^{2, 3} ; Kopp P² ; Chabert M² ; Mandel P²
Source: Journal of Neurochemistry Published:1994

Abstract

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 ∼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.