Guang Han1, Tom Magee, Omid Khorram. 1. Department of Obstetrics and Gynecology, Harbor-UCLA Medical Center, LA Biomedical Institute, Torrance, California, USA.
Abstract
OBJECTIVE: To examine the influence of estrogen on the expression of nitric oxide synthase (NOS) isoforms in human endometrial surface epithelial cell line (HES) and primary endometrial cells. DESIGN: Laboratory-based investigation. SETTING: Academic center. INTERVENTION(S): The expression of NOS isoform protein levels and mRNA was determined following estrogen/progesterone stimulation. MAIN OUTCOME MEASURE(S): NOS protein and mRNA levels in HES and primary endometrial cells. RESULT(S): Estradiol 17-beta (E2) induced a dose- and time-dependent increase in the expression of eNOS mRNA and protein and iNOS protein in HES cells which could be blocked by the estrogen receptor antagonist ICI 182,780. Estradiol increased the expression of eNOS mRNA and protein in primary endometrial cells. Estrogen also induced phosphorylation of eNOS which could not be blocked by ICI 182,780. Progesterone in physiologic concentrations augmented the effect of estrogen on the expression of both eNOS and peNOS but not of iNOS. ICI 182,780 in high concentrations stimulated the expression of iNOS protein while inhibiting eNOS. CONCLUSION(S): Estradiol through a genomic mechanism stimulates the expression of NOS isoforms in endometrial derived primary and HES cells. This effect is potentiated by progesterone.
OBJECTIVE: To examine the influence of estrogen on the expression of nitric oxide synthase (NOS) isoforms in human endometrial surface epithelial cell line (HES) and primary endometrial cells. DESIGN: Laboratory-based investigation. SETTING: Academic center. INTERVENTION(S): The expression of NOS isoform protein levels and mRNA was determined following estrogen/progesterone stimulation. MAIN OUTCOME MEASURE(S): NOS protein and mRNA levels in HES and primary endometrial cells. RESULT(S): Estradiol 17-beta (E2) induced a dose- and time-dependent increase in the expression of eNOS mRNA and protein and iNOS protein in HES cells which could be blocked by the estrogen receptor antagonist ICI 182,780. Estradiol increased the expression of eNOS mRNA and protein in primary endometrial cells. Estrogen also induced phosphorylation of eNOS which could not be blocked by ICI 182,780. Progesterone in physiologic concentrations augmented the effect of estrogen on the expression of both eNOS and peNOS but not of iNOS. ICI 182,780 in high concentrations stimulated the expression of iNOS protein while inhibiting eNOS. CONCLUSION(S): Estradiol through a genomic mechanism stimulates the expression of NOS isoforms in endometrial derived primary and HES cells. This effect is potentiated by progesterone.