[Activation of poly(ADP-ribose)-polymerase inhibits apoptosis of thymocytes, caused by short-wave ultraviolet radiation].
The effect of (i) aphidicolin, a specific inhibitor of delta- and epsilon-polymerases, and nucleotide excision repair; (ii) 3-aminobenzamide, an inhibitor of poly(ADP-ribose) polymerase and base excision repair; and (iii) actinomycin D and cycloheximide, inhibitors of protein and RNA synthesis, respectively, on the induction of suppression of apoptosis of rat thymocytes by different doses of short-wavelength ultraviolet radiation was studied by flow cytometry. 3-Aminobenzamide suppressed the inhibition of apoptosis induced by the doses of short-wavelength ultraviolet radiation higher than 20 J/m2, increasing the cell death to a maximum. Thus, the inhibition of apoptosis by high short-wavelength ultraviolet radiation doses depends on the status of poly(ADP-ribose) polymerase and is prevented by 3-aminobenzamide. As opposed to 3-aminobenzamide, aphidicolin did not affect the cell death at short-wavelength radiation doses higher than 10 J/m2 but induced the apoptosis of unirradiated cells and cells irradiated with short-wavelength ultraviolet radiation doses lower than 10 J/m2. The inhibitors of protein and RNA synthesis cycloheximide and actinomycin D prevented the induction of apoptosis caused by low and medium doses but did not abolish the apoptosis-inhibiting activity of high doses of short-wavelength ultraviolet radiation.
Dolgachev
V A
VA
Institute of Cell Biophysics, Russian Academy of Sciences, Pushchino, Moscow Region, Russia.
Afanas'ev
V N
VN
Dolgacheva
N N
NN
Pechatnikov
V A
VA
D000818:Animals; D016590:Aphidicolin / Q000494:pharmacology; D017209:Apoptosis; D001549:Benzamides / Q000494:pharmacology; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D011065:Poly(ADP-ribose) Polymerases / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013950:Thymus Gland / Q000166:cytology / Q000201:enzymology / Q000528:radiation effects*; D014466:Ultraviolet Rays
D001549:Benzamides; D004791:Enzyme Inhibitors; D016590:Aphidicolin; C025160:3-aminobenzamide; D011065:Poly(ADP-ribose) Polymerases