Seminal Vesicles

PurposeThis study analyses seminal vesicle displacement relative to the prostate and in relation to treatment time.MethodA group of eleven patients undergoing prostate cancer radiotherapy were imaged with a continuous 3 T cine-MRI in the standard treatment setup position. Four images were recorded every 4 seconds for 15 minutes in the sagittal plane and every 6.5 seconds for 12 minutes in the coronal plane. The prostate gland and seminal vesicles were contoured on each MRI image. The coordinates of the centroid of the prostate and seminal vesicles on each image was analysed for displacement against time. Displacements between the 2.5 percentile and 97.5 percentile (i.e. the 2.5% trimmed range) for prostate and seminal vesicle centroid displacements were measured for 3, 5, 10 and 15 minutes time intervals in the anterior-posterior (AP), left-right (LR) and superior-inferior (SI) directions. Real time prostate and seminal vesicle displacement was compared for individual patients.ResultsThe 2.5% trimmed range for 3, 5, 10 and 15 minutes for the seminal vesicle centroids in the SI direction measured 4.7 mm; 5.8 mm; 6.5 mm and 7.2 mm respectively. In the AP direction, it was 4.0 mm, 4.5 mm, 6.5 mm, and 7.0 mm. In the LR direction for 3, 5 and 10 minutes; for the left seminal vesicle, it was 2.7 mm, 2.8 mm, 3.4 mm and for the right seminal vesicle, it was 3.4 mm, 3.3 mm, and 3.4 mm. The correlation between the real-time prostate and seminal vesicle displacement varied substantially between patients indicating that the relationship between prostate displacement and seminal vesicles displacement is patient specific with the majority of the patients not having a strong relationship.ConclusionOur study shows that seminal vesicle motion increases with treatment time, and that the prostate and seminal vesicle centroids do not move in unison in real time, and that an additional margin is required for independent seminal vesicle motion if treatment localisation is to the prostate.

BackgroundTo analyze interfraction motion of seminal vesicles (SV), and its motion relative to rectal and bladder filling.Methods and materialsSV and prostate were contoured on 771 daily computed tomography "on rails" scans from 24 prostate cancer patients undergoing radiotherapy. Random and systematic errors for SV centroid displacement were measured relative to the prostate centroid. Margins required for complete geometric coverage of SV were determined using isotropic expansion of reference contours. SV motion relative to rectum and bladder was determined.ResultsSystematic error for the SV was 1.9 mm left-right (LR), 2.9 mm anterior-posterior (AP) and 3.6 mm superior-inferior (SI). Random error was 1.4 mm (LR), 2.7 mm (AP) and 2.1 mm (SI). 10 mm margins covered the entire left SV and right SV on at least 90% of fractions in 50% and 33% of patients and 15 mm margins covered 88% and 79% respectively. SV AP movement correlated with movement of the most posterior point of the bladder (mean R2 = 0.46, SD = 0.24) and rectal area (mean R2 = 0.38, SD = 0.21).ConclusionsConsiderable interfraction displacement of SV was observed in this cohort of patients. Bladder and rectal parameters correlated with SV movement.

BackgroundProstasomes are suggested to be produced in the prostate gland. Although biochemical studies support this, some immunohistochemical findings indicate that also the seminal vesicles could be a source of prostasomes. Therefore, we have compared the secretion of the vesicles with that of the prostate using biochemical and ultrastructural techniques.MethodsUltracentrifuged pellets of substance from seminal vesicle secretions were analysed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and flow cytometry. The secretory cells of the seminal vesicles were examined with transmission electron microscopy. These findings were then compared with published results from similar studies of the prostate secretory cells.ResultsIn SDS-PAGE, the seminal vesicle pellets lacked the three prostasome-characteristic CD-markers, namely CD10, CD13, and CD26, but expressed two proteins of about 55 kDa and 70 kDa, corresponding to clusterin and heat shock protein (HSP70). Flow cytometry showed the presence of secretion particles in the seminal pellet, although of a smaller size than that of the prostasomes. Electron microscopy of the luminal part of the cells in the seminal vesicles demonstrated many secretion granules, each enclosed in a vesicle with a size of about 1 microm.ConclusionsPelleted seminal vesicle secretion is different to prostate secretion in several ways. No prostasome characteristics were detected in the pelleted seminal vesicle secretion.

Human seminal vesicles present basal release of epithelium-derived 6-nitrodopamine (6-ND) and this catecholamine potentiates noradrenaline-induced contractions. Since nitric oxide synthase (NOS) activation is a determining factor involved in 6-ND biosynthesis, this study aimed to investigate which NOS isoform is responsible for the 6-ND release in mouse isolated seminal vesicles (MISV). Male control, eNOS-/-, NOS-/-, iNOS-/-, and e/n/iNOS-/- mice were used. 6-ND release was evaluated by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). MISV contractility was assessed following electric-field stimulation (EFS) or construction of concentration-response curves to catecholamines. MISV from control, eNOS-/-, nNOS-/-, iNOS-/-, and e/n/iNOS-/- mice exhibited basal release of 6-ND, but 6-ND release from eNOS-/- and e/n/iNOS-/- was significantly reduced compared to control and nNOS-/- mice. Epithelium removal in MISV from control mice significantly reduced 6-ND levels. EFS (2-32 Hz) induced frequency-dependent MISV contractions in all groups, but the contractions from eNOS-/- and e/n/iNOS-/- mice were significantly decreased compared to control groups. In vitro l-NAME treatment or epithelium removal significantly reduced EFS-induced contractions. Pre-incubation of MISV with 6-ND (1-100 nM) significantly potentiated both EFS- and noradrenaline-induced contractions, whereas pre-incubation with noradrenaline, adrenaline, and dopamine did not affect the EFS-induced responses. Immunohistochemistry and fluorescence in situ hybridization (FISH) assays revealed positivity for tyrosine hydroxylase and eNOS in the epithelium and endothelium of the seminal vesicles. In conclusion, MISV releases epithelium-derived 6-ND, and its biosynthesis involves eNOS activation. The finding that 6-ND markedly amplified the noradrenaline-induced contractions indicates that epithelium-derived 6-ND acts as a major modulator of MISV contractility.