Hormonal replacement therapy and urinary problems as evaluated by ultrasound and color Doppler

Effects of endogenous ovarian estrogen versus exogenous estrogen replacement on blood flow and ERβα and ERβ levels in the bladder

OBJECTIVE

Determine the effect of endogenous estrogen versus estrogen replacement therapy (ERT) on bladder blood flow (BBF) and estrogen receptors (ERs).

METHODS

BBF was determined with radiolabeled microspheres in luteal, follicular, pregnant, oophorectomized (Ovx) sheep, and Ovx sheep with ERT. Estrogen receptors (ERalpha, ERbeta) were quantified using Western blot analysis.

RESULTS

Compared to luteal and follicular ewes, BBF was reduced in pregnancy and following oophorectomy. Estrogen replacement therapy in Ovx sheep restored BBF to luteal levels. Estrogen receptor alpha predominated, whereas ERbeta was not detectable. Estrogen receptor-alpha levels were unaffected by the ovarian cycle and increased in pregnancy, as well as in Ovx sheep with and without chronic ERT.

CONCLUSION

The combination of diminished BBF and elevated ERalpha levels in both pregnant and Ovx sheep suggests an inverse relationship between BBF and ERalpha in the bladder. Although chronic ERT in Ovx sheep restored BBF, it did not restore ERalpha back to luteal levels.

Transdermal HRT and Doppler findings in normotensive and hypertensive postmenopausal patients

OBJECTIVE

To evaluate the effects of transdermal hormone replacement therapy (HRT) on plasma viscosity, serum levels of thromboxane B2 (TXB2) and vascular impedance in the uterine, bladder wall, internal carotid and ophthalmic arteries in normotensive and hypertensive postmenopausal patients.

METHODS

Thirty postmenopausal patients underwent continuous estradiol transdermal supplementation at a dose of 50 microg/day and 12-day courses of medroxyprogesterone acetate 10 mg/day every 2 months. The women were divided into two groups according to their blood pressure: normotensive women (Group 1, n=14) and hypertensive subjects (Group 2, n=16). Before starting HRT and after 6 months of therapy, the patients underwent: transvaginal ultrasonographic examination of the pelvic organs; Doppler examination of the blood flow velocities in the uterine, bladder wall, internal carotid and ophthalmic arteries; and analysis of plasma viscosity and plasma TXB2.

RESULTS

After 6 months of HRT plasma viscosity had decreased in both groups (mean reduction in Group 1, (14+/-1)%, P=0.005; mean reduction in Group 2, (10+/-1)%, P=0.005) as had the TXB2 levels (mean reduction in Group 1, (93+/-2)%, P<0.001; mean reduction in Group 2, (92+/-3)%, P<0.001). The mean percentage reduction in plasma viscosity was smaller in hypertensive women than in normotensive women (P<0.05). There was also a significant reduction in vascular impedance in the uterine artery (mean reduction in Group 1, (16+/-1)%, P=0.005; mean reduction in Group 2, (19+/-1)%, P=0.005), the bladder wall arteries (mean reduction in Group 1, (23+/-2)%, P=0.005; mean reduction in Group 2, (18+/-1)%, P=0.005), the internal carotid artery (mean reduction in Group 1, (25+/-1)%, P=0.005; mean reduction in Group 2, (26+/-1)%, P=0.005) and the ophthalmic artery (mean reduction in Group 1, (24+/-2)%, P=0.005; mean reduction in Group 2, (16+/-1)%, P=0.005). The percentage reduction in vascular impedance did not differ significantly between the two groups.

CONCLUSIONS

Our results show that transdermal HRT is effective in reducing plasma viscosity, TXB2 levels and vascular impedance in the peripheral and central vessels both in normotensive and hypertensive postmenopausal patients.

Influence of estradiol on micturition thresholds in the rat: involvement of the hypogastric nerve

Studies have shown that the severity of bladder hyperreflexia induced by acute bladder inflammation varies with the ovarian cycle. These results suggest that the hyperreflexia is modulated by ovarian hormones. Other studies have suggested that such modulation involves the bladder's sympathetic innervation. These hypotheses were tested by assessing the development of bladder hyperreflexia in urethane-anesthetized rats subjected to different hormonal manipulations with or without bilateral hypogastric neurectomy (HYPX). The groups included sham ovariectomy (sham OVX), ovariectomy (OVX), OVX with estradiol replacement (OVX+E), OVX+HYPX, and OVX+HYPX+E. Assessments were performed using repeated cystometrograms (CMGs) to measure micturition thresholds (MT) before and hourly for 3 h after intravesicular treatment with 50% turpentine oil (or olive oil in an OVX+E control group). In the uninflamed bladder, treatment with estradiol increased MTs in the OVX+E group compared with the OVX group. As expected, bladder inflammation induced bladder hyperreflexia in sham OVX rats (studied in estrus). This hyperreflexia was eliminated by OVX and restored by either estradiol replacement or HYPX. Combining estradiol replacement and HYPX (i.e., OVX+E+HYPX) did not increase the severity of bladder hyperreflexia compared with either manipulation alone. These results indicate that the bladder hyperreflexia that is induced by bladder inflammation requires the presence of estradiol and suggest that this hormonal modulation is exerted via the sympathetic control of the bladder, possibly via an increase of beta-adrenergic inhibitory actions on the detrusor muscle. Similar mechanisms may contribute to bladder disorders in postmenopausal women.

Development of nocturia in relation to health, age and the menopause

OBJECTIVES

To analyse the relationship between nocturia, age, the menopausal transition, parturition and hormone replacement treatment (HRT) in women.

MATERIAL AND METHODS

A questionnaire study was carried out in 3669 randomly selected women (out of 6000 invited) in the County of Jämtland, Sweden. Questions were asked about health, the occurrence of somatic diseases and symptoms, habits, health care and medication.

RESULTS

In univariate analyses age, menopausal state and HRT, but not parturition, were associated with increased nocturia. In a multiple logistic regression analysis, independent correlates for two or more nocturnal micturition episodes versus no more than one episode were: health, poor versus good 2.9 (2.1-3.8); <5 years after the menopause versus before 1.8 (1.3-2.5); 5-9 years after the menopause versus before 2.1 (1.5-3.0); > or =10 years after the menopause versus before 3.1 (2.3-4.2). Age and HRT were deleted by the logistic regression model.

CONCLUSION

The present data indicate that menopausal state, but not age, parturition and HRT are independent correlates of nocturia in 40-64-year-old women.

Effects of hormone replacement therapy on plasma viscosity and Doppler variations in postmenopausal non-smokers and heavy smokers

OBJECTIVES

To evaluate the effects of transdermal hormone replacement therapy (HRT) on some biological cardiovascular risk factors, specifically thromboxane B2 level and plasma viscosity. Furthermore, we investigated Doppler flow modifications at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries, and evaluated whether there were significant differences, in the examined parameters, between postmenopausal women who were non-smokers and heavy smokers.

METHODS

Forty-three postmenopausal women (age 53.6 +/- 3.3 years, mean +/- standard deviation) participated in the study and were divided into two groups (Group I: n = 21, normal controls; and Group II: n = 22, heavy smokers). Patients were treated with continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every 2 months. They were studied at baseline and after 6 months (in the estrogen-only phase of the cycle).

RESULTS

Results showed a beneficial effect of hormone substitution after 6 months of therapy. Plasma viscosity decreased significantly after 6 months of therapy both in non-smokers and heavy smokers (-18% and -14%, respectively). Plasma levels of thromboxane B2, which were similar at baseline, underwent a dramatic reduction in both Group I and Group II (-93% and -88%, respectively). Doppler assessment of pulsatility index at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries showed a significant reduction in vascular impedance at the end of treatment in both groups. However, the treatment was significantly less beneficial, in terms of the analyzed factors, in heavy smokers.

CONCLUSIONS

Cigarette smoking represents a cardiovascular risk factor that can only partially be modified by the administration of transdermal HRT.

Time since menopause does not affect plasma viscosity, plasma thromboxane levels and Doppler findings

OBJECTIVES

To evaluate whether the use of transdermal hormone replacement therapy (HRT), in women within 5 years of menopause compared with women who were postmenopausal for > 5 years, would significantly influence thromboxane B2 levels, plasma viscosity and Doppler flow parameters at the level of the uterine, internal carotid, ophthalmic and bladder wall arteries.

METHODS

Thirty-five normal-weight (body mass index > 19 and < 25 kg/m(2)) postmenopausal women (age 54.6 +/- 3.9 years, mean +/- standard deviation) participated in the study and were divided into two groups (Group I: n = 19, time since menopause < 5 years; and Group II: n = 16, time since menopause > 5 years). Patients were treated with a continuous estradiol transdermal supplementation and 12-day courses of medroxyprogesterone acetate every 2 months. They were studied at baseline and after 6 months (in the estrogen-only phase of the cycle).

RESULTS

Results showed a beneficial effect of hormone substitution after 6 months of therapy. Baseline plasma viscosity was similar in both groups, and decreased significantly after therapy in both Group I (-17.5%) and Group II (-15.6%). Plasma levels of thromboxane B(2) were similar at baseline and diminished equally in Group I and Group II (-85.6% and -85.2%, respectively) after treatment. Doppler assessment of the pulsatility index at the level of uterine, internal carotid, ophthalmic and bladder wall arteries showed no differences between groups at baseline and revealed a significant reduction of vascular impedance at the end of the treatment in both groups.

CONCLUSIONS

Time since menopause does not affect the potential hemodynamic benefits of HRT in normal-weight women.

Transdermal hormone replacement therapy and Doppler findings in normal and overweight postmenopausal patients

The aim of this study was to evaluate the effects of transdermal hormone replacement therapy on some biological cardiovascular risk factors, specifically the thromboxane B2 levels, plasma viscosity and the lipid profile. Furthermore, we investigated the Doppler flow modifications at the level of the uterine artery, the internal carotid, the ophthalmic and the bladder wall arteries, and we finally evaluated whether there were significant differences in the examined parameters between normal and overweight postmenopausal women. Forty-five postmenopausal women (mean age+/-standard deviation, 53.5+/-3.8 years) participated in the study and were divided into two groups (27 with a body mass index of < 25 kg/m2 and 18 with a body mass index of > 25 kg/m2). Patients were treated with a continous estradiol transdermal supplement and a 12-day course of medroxyprogesterone acetate every 2 months, and were studied at baseline and after 6 months (in the estrogen-only phase of the second cycle). Our results showed a beneficial effect of hormone substitution on plasma viscosity, thromboxane B2 levels and lipid profile after 6 months of therapy and significant improvements of Doppler flow parameters in the examined vessels. Furthermore, we observed a lower impact of the treatment in overweight women. In conclusion, obesity represents an additional cardiovascular risk condition and it can only partially be modified by the administration of hormone replacement therapy.

Power Doppler ultrasound imaging for quantification of urinary bladder neck blood flow changes

This study was designed to evaluate power Doppler imaging for assessment of urinary bladder neck blood flow in comparison with laser Doppler flowmetry (LDF) in an animal model. Transrectal power Doppler ultrasound (US) and LDF of the urinary bladder neck were performed in three anesthetized pigs during comparative cystometry. Normal saline (NaCl) was used for the first run, followed by a second run with 0.2 mol/L potassium chloride (KCl). Standardized sonographic equipment settings (Acuson Sequoia 512); MountainView, CA) were used for power Doppler imaging. Computer-assisted calculation of color pixel density (CPD) of power Doppler images was performed using Scion Image) software image analysis. Tissue perfusion units (TPU) were measured using a BLF21 laser Doppler flowmeter (Transonic Systems Inc., Ithaca, NY, USA). The power Doppler results were compared with the findings obtained by LDF. NaCl filling resulted in a mean CPD increase at the bladder neck from 18.65 (+/- 1.78) at empty bladder to 37.8 (+/- 1.84) at 100 mL and to 88.32 (+/- 1.35) at full bladder capacity (C(max)) of 270 mL, respectively. With KCl filling, a mean CPD increase from 18.65 (+/- 1.78) to 59.63 (+/- 0.5) at 100 mL and 110.82 (+/- 2.98) at full bladder capacity (270 mL) was observed. The CPD increase was significantly higher for KCl than with NaCl (p < 0.001). With NaCl filling, bladder neck blood flow increased from 22 TPU (empty) to 46 TPU (100 mL) and 62.5 TPU at C(max), compared to 22 TPU, 50 TPU and 102.5 TPU with KCl. CPD and TPU measurements showed a strong correlation at p = 0.01. In conclusion, transrectal power Doppler US image quantification is a feasible and accurate method for assessing blood flow changes in the urinary bladder neck.

Endocrine status affects bladder size and postvoid residual urinary volume in mice

Urine is one of the major media for intraspecific chemical communication in mice. The urination pattern is dependent both on the mice's hormonal and social status. The urination pattern and the morphology of the urinary tract were examined in mice following hormonal manipulations. In the first experiment, we compared pairs of intact and castrated males: intact males urinated earlier when exposed to a new environment, with a greater number of drops that were smaller than those of castrated males. In the second experiment, groups of intact males, castrated, testosterone-supplemented castrated, and isolated intact males were compared. The micturition pattern of isolated intact males consisted of numerous small droplets of urine, with a high volume of urine retained in the bladder after voiding. This also applied to grouped intact males and testosterone-treated castrated mice, while castrated mice voided a larger fraction of bladder content. Bladder weight was higher in intact males and testosterone-treated castrated males, as compared to castrated males. In the third experiment, ovary-intact and testosterone-treated intact females were compared. Testosterone-treated ovary-intact females retained a larger quantity of urine in the bladder and also had a larger bladder compared to ovary-intact females. Testosterone thus induces the morphological modifications of the urinary tract necessary for the dominant male urination pattern, which is an increase in postvoid urinary residual volume and bladder weight. As evidenced from the comparison of histological sections from intact, castrated, and testosterone-treated castrated males, the increase in bladder weight was mainly due to the bladder muscular mass.