P-511

gene, including the delta F508 mutation, which represents about 70% of CF mutations. The additional 24 mutations in the panel increase the detection rate to 90% in Caucasians. The sensitivity of testing using the 25 mutation panel varies by racial and ethnic group. Although testing will allow refined risk assessment, negative test results reduce the risk but do not eliminate it. This concept is challenging to convey to patients and requires careful genetic counseling. MATERIALS AND METHODS: The case report of a woman affected with CF and her husband, who are undergoing IVF with surrogacy, both whom had been inadequately screened for CF, illustrates the complexities of CF screening. Offering thorough and appropriate screening ensures that couples undergoing IVF can take full advantage of technologies such as PGD when appropriate. RESULTS: none. CONCLUSION: Working in partnership with a genetic counselor can help ensure that appropriate testing is being ordered and that results are being interpreted correctly. Supported by: None

HORMONE SYNTHESIS AND ACTION P-511 DIFFERENTIAL CELL SPECIFIC MODULATION OF HOXA10 BY ESTROGEN AND SP1 RESPONSE ELEMENTS. J. Martin, M. B. Taylor, E. Akbas, H. S. Taylor. Yale Univ. School of Medicine, New Haven, CT. OBJECTIVE: HOX genes are highly evolutionarily conserved regulators of embryonic development. HOXA10 continues to regulate differentiation of the adult reproductive tract and mammary gland in response to sex steroids. HOXA10 estrogen response elements ERE1 and ERE2 were recently characterized and are differentially expressed in response to 17Bestradiol (E2) or diethylstilbestrol (DES) in uterine cells. Here we demonstrate that estrogen responsive HOXA10 expression is not only ligand specific but cell type specific. DESIGN: In vitro experiment. MATERIALS AND METHODS: HOXA10 expression in response to 10(-8) M estradiol was evaluated in both endometrial Ishikawa cells and breast MCF-7 cells using qRT-PCR. Nested segments of the HOXA10 promotor were tested for estrogen responsiveness in transient transfection reporter assays. Electrophoretic gel mobility shift assays (EMSA) were used to detect ER binding to putative EREs. Immunohistochemistry on endometrial biopsy specimens was used to localize Specificity protein one (SP1) expression. RESULTS: Estradiol drove HOXA10 expression in both endometrial and breast cells. Reporter assays identified two putative EREs and one SP1 binding site that drove estrogen responsive expression. In EMSA the two EREs, but not the SP1 site, bound both ER ␣ and ␤. In reporter assays both EREs and the SP1 site demonstrated tissue specificity; transiently transfected uterine Ishikawa cells or breast MCF-7 cells showed differential responses to E2 treatment. SP1 expression was localized to perivascular regions in secretory endometrium. CONCLUSION: We identified two EREs and a novel SP1 binding site that contribute to E2 mediated HOXA10 expression. Each response element (SP1 site, ERE1 and ERE2) drove distinct differential expression in each cell type. Tissue specificity inherent to the ERE imparts distinct E2 responses in different estrogen responsive tissues. Additionally localized SP1 expression at the earliest sites of decidualization imply that it may regulate early and focal HOXA10 expression within the endometrium. Endometrial HOXA10 expression is regulated in a spatial and cell specific manner by three enhancers in its 5⬘ regulatory region; this targeted regulation likely directs the specific role of HOXA10 in endometrial receptivity. Supported by: NIH HD 36887

P-512 ENDOGENOUS POSTMENOPAUSAL ANDROGENS AND REGIONAL BODY COMPOSITION. C. L. Casey, M. J. Toth, M. E. Dixon, D. Scarano, P. R. Casson. Univ. of Vermont, Burlington, VT; Univ. of Toronto, Toronto, ON, Canada.

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Abstracts

OBJECTIVE: In men, androgens have beneficial effects on a wide range of metabolic and morphometric indices. The role of androgens in postmenopausal women is uncertain. We previously reported that endogenous postmenopausal androgens correlate with greater exercise tolerance, increased insulin sensitivity, and decreased total body fat. The objective of this study was to determine the relationship between postmenopausal androgen levels and regional body composition in the same cohort. Our hypothesis was that higher postmenopausal circulating testosterone levels correlate to decreased visceral fat and increased thigh muscle area. DESIGN: Cross-sectional cohort study. MATERIALS AND METHODS: A total of 23 healthy, 50-70 year old, nonsmoking, nonhirsute, normal weight postmenopausal (⬎3 years, FSH ⬎50 mIU/ml, surgical or natural) women participated. They had been on no hormone replacement therapy, and had no history of infertility, cycle irregularity or hyperandrogenemia. Total, subcutaneous and visceral abdominal fat was calculated computed tomography (CT) scan at the L4-L5 level and total mid-thigh muscle and fat content. Fasting serum testosterone (T), free T, androstendione (⌬4A) and dehydroepiandrosterone (DHEA) levels were batch assayed using a radioimmunoassay (RIA) with preassay chromatographic separation. Sex hormone binding globulin (SHBG) was measured with direct chemiluminescent immunoassay. Correlations between abdominal fat, thigh fat, and thigh muscle content and these serum markers were performed by using Pearson correlation coefficients. RESULTS: There were no significant correlations between T, free T or SHBG with any aspect of regional body composition. However, increasing ⌬4A levels trended towards a negative correlation with visceral fat and a positive correlation to subcutaneous abdominal fat (R⫽-0.397 and 0.397, p0.061 and 0.061, respectively; both fat depots expressed as a % of total abdominal fat). DHEA was positively related to thigh fat (R⫽0.490, p⫽0.018). CONCLUSION: In healthy postmenopausal women without a history of PCOS, higher endogenous ⌬4A levels were related to lower levels of visceral fat. Moreover, increased ⌬4A and DHEA are associated with increased abdominal and thigh subcutaneous fat, respectively. These relationships may suggest a physiologically important role for androgens and their precursors in women in regulating beneficial patterns of regional fat deposition. Supported by: Funded in part by NIH RR-00109.

P-513 CHANGES IN GHRELIN AND ADIPOCYTOKINES LEVELS IN OVARIECTOMIZED PREMENOPAUSAL WOMEN TREATED WITH ESTROGEN. K. Dafopoulos, N. Chalvatzas, I. Kristo, A. Kallitsaris, I. Mademtzis, I. E. Messinis. Univ. of Thessalia, Larissa, Greece. OBJECTIVE: To investigate the effect of ovariectomy and exogenous estrogen administration on ghrelin, adiponectin and resistin levels in premenopausal women. DESIGN: Experimental study in a University hospital setting. MATERIALS AND METHODS: Eight normally cycling women were included in the study. Age and body mass index (BMI) of the women ranged between 42 and 48 years and 21.3 and 34.2 kg/m2 respectively. Each woman was investigated in two cycles, i.e. cycle-1 (control) and cycle-2 in which total abdominal hysterectomy plus bilateral salpingooophorectomy was performed under general anesthesia for benign uterine lesions. In cycle-2, the operation was performed on cycle day 3. Between the two cycles there was a month’s break. In both cycles, the women received estradiol (E2) through skin patches at the dose of 100 ␮g on cycle day 3 (0900 h) and 150 ␮g on cycle days 4 and 5. In cycle-2, the first E2 patch was applied immediately after the operation. Blood samples were obtained every morning (0800), after overnight fasting, from cycle day 3 until cycle day 9. In all blood samples, ghrelin, adiponectin, resistin, E2, progesterone, FSH and LH were measured. Statistical analysis was performed by repeated measures one way analysis of variance, paired t-test and Pearson’s correlation. RESULTS: In both cycles, E2 values increased similarly to preovulatory levels within 3 days (p⬍0.001). As a result, the women displayed both a negative and a positive feedback effect on FSH and LH levels. Serum adiponectin and resistin levels did not show any significant changes throughout the experimental period in both cycles. The levels of these two adipocytokines did not differ significantly between the two cycles at all time points. Serum ghrelin levels in cycle-1 showed no significant changes from the onset to the end of the experiment. In contrast, in cycle-2 ghrelin levels increased gradually and significantly from cycle day 3 (4.1 ⫾ 0.9 ng/ml) to

Vol. 86, Suppl 2, September 2006