PERICONCEPTIONAL ZINC-DEFICIENCY AFFECTS UTERINE H-3 ESTRADIOL BINDING IN MICE

To better define the mechanisms by which zinc (Zn) deficiency influenc es periconceptional development, we examined the effects of this devel opmental insult on uterine estrogen metabolism. CD-1 mice were assigne d to 1 of 3 groups (Low Zn, LZ; Control, C; or Replete, R) and fed eit her a low Zn (less than or equal to 0.3 mu g Zn/g) or control diet (47 mu g Zn/g) 5 days prior to gestation day (GD) 0 and continuing up to GD 4 during early pregnancy. Mice in the R group were fed the low Zn d iet until GD 1 after which they were fed the control diet. Uterine H-3 -estradiol binding in vivo was measured on GD 2, GD 3, and GD 4. Bindi ng was similar among groups on GD 2 and GD 3, but was lower on GD 4 in LZ mice than in C and R mice (61% of control value). On GD 4, uterine H-3-estradiol binding in vitro was measured and was lower in LZ mice than in C and R mice (63-74% of control values); the reduction in bind ing was due to lower receptor number. Thus, Zn deficiency can result i n a reduction in uterine estradiol receptors and estradiol binding. (C ) 1995 Wiley-Liss, Inc.