Abstract |
To assess the effect of ovarian steroid hormones on enzyme activity, adenosine diphosphoribosyl transferase (ADPRT) was measured in endometrial nuclei isolated on estrus and on d 4 from rats ovariectomized on estrus (d 0) and treated d 0-3 with vehicle, 1 microg estrone/d (E), 1 mg progesterone on d 0 and 2 mg d 1-3 (P), or the 2 hormones combined (E+P). Decidual induction in rats treated with E+P through d 8 demonstrated the ability of the combination treatment to support a decidual response comparable to that of pseudopregnancy. Characteristics of ADPRT were assessed by the determination of assay optima, and the identity of the reaction product as poly(ADP-ribose) was confirmed. Deoxyribonuclease-stimulated activity (total) was higher than non-stimulated ADPRT activity (endogenous) in all assays except on estrus. Estrone treatment produced an increase in ADPRT activity accompanied by increased DNA content, tissue mass, and total protein. (Copyright (c) 1989 The Endocrine Society.) |