Studies on Deoxyribonucleic Acid Synthesis in Uteri of Immature Mouse[*]

Abstract

Nicotinamide and 17β-estradiol were administered to immature mice and poly (adenosine diphosphate ribose) (ADP-ribose) synthetase activity and deoxyribonucleic acid (DNA) synthesis of uterine nuclei were measured. 17β-estradiol increased poly (ADP-ribose) synthetase activity and DNA synthesis of uterine nuclei. The synthetase activity of uterine chromatin was also elevated. The incorporation of [³H] thymidine into uterine DNA which was stimulated by 17β-estradiol was blocked by nicotinamide administration. Moreover, nicotinamide added to the incubation medium inhibited poly (ADP-ribose) synthetase activity of isolated uterine nuclei. The present results suggest that the inhibition of DNA synthesis induced by nicotinamide may be related to its effect on (ADP-ribose) synthetase activity.

Key words

17β-Estradiol-DNA Synthesis - Uterus Nicotinamide - Poly (Adenosine Diphosphate Ribose) Synthesis

1 Supported by research grant No. PO1 HDO5671-01 from The National Institute of Child Health and Human Development

1 Supported by research grant No. PO1 HDO5671-01 from The National Institute of Child Health and Human Development

2 Present address: Dept. of Obstetrics and Gynecology, Osaka University Medical School, Osaka, Japan.

3 On leave from The Institute de Bioquimica, Universidad Austral, Valdivia, Chile