Quantitative MRI of the prostate and uterus in monkeys

Defining endometrial growth during the menstrual cycle with three-dimensional ultrasound

OBJECTIVE

To define the changes in endometrial morphometry that occur during the normal menstrual cycle and to examine the discriminatory power of volumetric analysis over conventional two-dimensional measurements in quantifying the effect of compounding factors on endometrial growth.

DESIGN

The design was that of a longitudinal observational study. Subjects were seen on an alternate-day basis until ovulation and then every four days until the next menstrual period.

SETTING

A University teaching hospital.

POPULATION

Thirty women with regular cycles and acceptable "normal", menstrual patterns.

METHODS

Three-dimensional ultrasound data were acquired and subsequently analysed by a single observer.

MAIN OUTCOME MEASURES

Endometrial thickness and volume.

RESULTS

Both endometrial volume and thickness increased significantly during the follicular phase (P < 0.001), reaching a plateau around the time of ovulation and remaining relatively stable throughout the luteal phase. These changes in endometrial thickness and volume were highly correlated (R(2)= 0.767; P < 0.001). Parity was associated with a significantly greater endometrial volume than nulliparity (4.159 vs 2.234 cm(3); P < 0.05).

CONCLUSIONS

This study has defined the relative and absolute changes in endometrial growth, both in terms of thickness and volume, throughout the normal menstrual cycle. These data provide a reference for future three-dimensional studies investigating menstrual disorders, pathophysiological change and subfertility.

Assessment of hormonally active agents in the reproductive tract of female nonhuman primates

Using the ovariectomized macaque model of postmenopausal women's health, we investigated the effects of long-term treatments (5 weeks-3 years) with estradiol, conjugated equine estrogens (CEE), esterified estrogens, progestins such as medroxyprogesterone acetate (MPA) and nomegestrol acetate, CEE + MPA, tamoxifen, soybean phytoestrogens (SPEs), a variety of putative selective estrogen receptor modulators (SERMs), and androgens. Agents tested were selected on the basis of beneficial effects on arteries and/or bone. Doses were scaled on a caloric or serum-concentration basis to approximate human clinical doses. We evaluated endometrial and mammary gland histopathology and morphometry and used immunohistochemistry to evaluate cell proliferation and expression of estrogen receptor alpha and progesterone receptor (PR). Both estradiol and CEE induced endometrial hyperplasia. MPA antagonized epithelial proliferation induced by CEE in endometrium and induced pseudodecidual stromal hyperplasia in some animals. Tamoxifen induced endometrial polyps, cystic hyperplasia, stromal fibrosis, and PR expression but not Ki-67 expression. SPEs were not estrogenic at dietary doses and antagonized estrogen-induced proliferation in the endometrium and breast. Nandrolone induced mucometra and an adenomyosis-like change. The potential SERM 17 alpha dihydroequilenin did not have uterotrophic or mammotrophic effects. In general, experimental findings in macaques have been predictive of outcomes in human clinical trials of the same agents.

Application of serial in vivo magnetic resonance imaging to evaluate the efficacy of endothelin receptor antagonist SB 217242 in the rat carotid artery model of neointima formation

BACKGROUND

Alleviating vascular restenosis after percutaneous transluminal angioplasty remains a formidable challenge. Although multiple factors have been implicated in the pathophysiology of this vascular remodeling disorder, only limited therapeutic success has been achieved. Endothelin (ET)-1 has recently been implicated in the pathogenesis of neointimal growth. We report the in vivo efficacy of SB 217242, a nonpeptide dual ET(A)/ET(B) receptor antagonist with high oral bioavailability, in the rat carotid artery balloon angioplasty model.

METHODS AND RESULTS

The lumen volumes of carotid arteries were estimated serially with magnetic resonance imaging (MRI) at baseline and at day 7 and day 14 after balloon catheter-induced denudation of the carotid arterial wall in the rat. Histomorphometric analysis was performed at day 14 after surgery to quantitate intimal hyperplasia. Statistical analysis was performed with ANOVA followed by post hoc Newman-Keuls multiple comparison test. In comparison to vehicle-treated animals, a 20% protection (P<0.05) from reduction was shown in the estimated lumen volume with long-term administration of SB 217242 (15 mg/kg BID p.o.). Histologic analyses indicated a 42% decrease (P<0.05) in neointimal growth. The MRI lumen volumes had a significant correlation with the corresponding histologic indices.

CONCLUSIONS

Serial MRI provides the opportunity to assess the progression of vascular lumen volume in vivo after balloon angioplasty. MRI measurements can, in conjunction with in vitro histologic measurements, contribute to the understanding of the actions of pharmacologic agents in experimental models of neointima formation. With the use of serial MRI and histologic measurements, it is demonstrated that protection from both lumen volume reduction and neointima formation is obtained in this model by use of a potent, nonpeptide dual ET(A)/ET(B) receptor antagonist, SB 217242. Furthermore, this study provides additional support to the implication of ET-1 in the pathophysiology of neointima formation.

Endometrial volume change during spontaneous menstrual cycles: volumetry by transvaginal three-dimensional ultrasound

OBJECTIVE

At present, only limited data are available on endometrial volume during the menstrual cycle. Most of these studies deal with animal models and use magnetic resonance imaging for volume measuring. The application of three-dimensional ultrasound in endometrial volume estimation is the subject of this study.

SETTING

Patients visiting the outpatient unit of the division of endocrinology and reproductive medicine of a university hospital.

PATIENT(S)

Twenty patients with a history of a normal menstrual cycle were selected.

INTERVENTION(S)

Ultrasound examinations were performed during a single menstrual cycle in addition to routine laboratory tests.

MAIN OUTCOME MEASURE(S)

Uterus-endometrial volume ratio.

RESULT(S)

Data from 18 patients could be evaluated. In 81 examinations the endometrium volume could be determined. Mean endometrial volume measured by three-dimensional ultrasound was 1.23 cm3. Mean uterus volume was 48.93 cm3. The change of the uterus-endometrial volume ratio showed a good correlation with the day of menstrual cycle. Quadratic regression analysis of volume and cycle length was R2 = 0.432.

CONCLUSION(S)

Three-dimensional ultrasound allows assessment of volume data of the female internal genitalia. In this study changes of the endometrial volume in menstrual cycles were measured. Additional studies are required to give information on the clinical impact of this new technique of endometrial volume estimation.