Vasa deferentia and associated structures of the male Panorpodes kuandianensis (Mecoptera: Panorpodidae)

The male reproductive system may provide significant evidence for the taxonomic and phylogenetic analyses of insects. However, current knowledge of the male reproductive system in Mecoptera is mainly concentrated on the external genitalia, and is rarely involved in the internal reproductive system. Here, we investigated the morphology and the fine structure of the vasa deferentia and associated structures of the male reproductive system of Panorpodes kuandianensis Zhong et al., 2011 (Panorpodidae) using light, scanning, and transmission electron microscopy. The male reproductive system of P. kuandianensis consists of a pair of symmetrical testes with three tubular testicular follicles, two epididymides, two distinctly partitioned vasa deferentia, a pair of mesadenia, one ejaculatory sac, and the external genitalia. A pair of expanded seminal vesicles are modified from the median part of the vasa deferentia, and evolve into secretory organs. The seminal vesicles have elongated cylindrical epithelial cells, which contain abundant secretory materials in the cytoplasm and form a small central lumen, likely serving a secretory function rather than provisionally storing sperm as in most other insects. Alternatively, the sperm are stored temporarily in the epididymis, the greatly coiled portion of the vasa deferentia. The morphology of the male reproductive system supports the close relationships of Panorpidae and Panorpodidae.

Intraoperative Observation during Total Extraperitoneal Repair (TEP)

We aim to observe and dissect the essential anatomical landmarks in totally extraperitoneal (TEP) procedures. Forty-six TEP procedures in 30 patients were prospectively performed in our department. During the dissection of the preperitoneal space, the following distances between landmarks were measured. D1: the distance from pubic symphysis to the arcuate line in the midline; D2: the distance from the inferior epigastric artery to the lateral border of the arcuate line (before sharp incision was performed); D3: as in D2 (but after sharp incision was performed); D4: the distance from the inferior epigastric artery to the crossing site of vas deferens and obliterated umbilical artery. Furthermore, the morphology of the posterior rectus sheath was documented. The corresponding distance between the anatomical landmarks varied greatly in each individual. D1: 8 ± 1.6 cm (range 4-10 cm). D2: 4.9 ± 0.8 cm (3.5-7 cm). D3: 6.8 ± 0.9 cm (5-9 cm). D4: 6.1 ± 1 cm (4.8-8.5 cm). Complete rectus sheath was found in 30.4 per cent (14/46) of the hernias. Anatomical variations were common in preperitoneal space. The crossing site of vas deferens and obliterated umbilical artery can serve as a landmark for dissection. Complete rectus was present in one-third of hernias, which necessitates a sharp incision for entering the correct lateral preperitoneal space.

Histological structure and age-related changes in the luminal diameter of the excurrent duct system of guinea cocks (Numida meleagris) and associated changes in testosterone concentrations

As little information is available on the reproductive system of guinea fowl (Numida meleagris), a study was conducted on 49 male guinea fowl to document the histological structure and developmental changes in the luminal diameter of the ducts within the excurrent duct system and associated changes in concentrations of testosterone. Age-related changes were analyzed using the Kruskal-Wallis test and medians separated by the Mann-Whitney U-test. Tubuli recti were clearly visible in the guinea fowl and the rete testes were both intracapsular and extracapsular. Regardless of age, the luminal diameter of the proximal ductuli efferentes was the largest, while that of the connecting duct was the smallest. The luminal diameter of all ducts within the epididymal region increased (P < 0.001) monthly until 20 wk of age, and then increased marginally every month thereafter. Peripheral testosterone concentrations also peaked at 20 wk of age and declined thereafter. In adult birds, the ductus deferens enlarged posteriorly, from an average of about 279 μm cranially to 678 μm caudally. Peripheral testosterone concentrations strongly and positively correlated with the luminal diameter of ducts within the excurrent duct system. The pattern of increase in the luminal diameter of all ducts followed the pattern of testosterone secretion in these birds, which indicates that testosterone concentrations may be closely related to the development of the excurrent duct system in male guinea fowl.

[Laparoscopic percutaneous extraperitoneal closure does not affect vas deferens orientation or testicular volume and perfusion]

OBJECTIVE

To investigate the influence of single-port laparoscopic percutaneous extraperitoneal closure (LPEC) on the orientation of the vas deferens and the volume and perfusion of the testis in pediatric patients undergoing inguinal hernia repair.

METHODS

A total of 92 consecutively enrolled boys diagnosed with unilateral inguinal hernia underwent single-port LPEC between June 2013 and June 2014. The orientation of the vas deferens and the testicular volume and perfusion of the patients were ultrasonographically assessed preoperatively and at 1 and 6 months after surgery.

RESULTS

All the surgical procedures were performed successfully without conversion or serious perioperative complications. Ultrasonography showed no angulation or distortion of the vas deferens on the surgical side during a six-month follow-up period. Similarly, no obvious changes were observed in the testicular volume or perfusion.

CONCLUSIONS

Single-port LPEC is safe and effective in the treatment of pediatric inguinal hernia and does not affect the orientation of the vas deferens or testicular volume and perfusion.

Long-Term Spatio-Temporal Trends of Organotin Contaminations in the Marine Environment of Hong Kong

Hong Kong imposed a partial restriction on application of organotin-based antifouling paints in 1992. Since September 2008, the International Maritime Organization prohibited the use of such antifouling systems on all sea-going vessels globally. Therefore, it is anticipated a gradual reduction of organotin contamination in Hong Kong’s marine waters. Using the rock shell Reishia clavigera as a biomonitor, we evaluated the organotin contamination along Hong Kong’s coastal waters over the past two decades (1990–2015). In 2010 and 2015, adult R. clavigera were examined for imposex status and analysed for tissue concentrations of six organotins. We consistently found 100% imposex incidence in female R. clavigera across all sites. Tissue triphenyltin (TPT) concentrations were high in most samples. A probabilistic risk assessment showed that there were over 69% of chance that local R. clavigera would be at risk due to exposure to phenyltins. Comparing with those of previous surveys (2004–2010), both imposex levels and tissue concentrations of organotins did not decline, while the ecological risks due to exposure to organotins were increasing. We also observed high concentrations of monobutyltin and TPT in seawater and sediment from locations with intense shipping activities and from stormwater or sewage discharge. Overall, organotins are still prevalent in Hong Kong’s marine waters showing that the global convention alone may be inadequate in reducing organotin contamination in a busy international port like Hong Kong. Appropriate management actions should be taken to control the use and release of organotins in Hong Kong and South China.

Confocal microscopy reveals uniform male reproductive anatomy in eriophyoid mites (Acariformes, Eriophyoidea) including spermatophore pump and paired vasa deferentia

Male internal genitalia of eriophyoid mites comprise cuticle lined (anterior genital apodeme, genital chamber and ductus ejculatorius) and soft (paired vasa deferentia and single testis) organs. Three-dimensional reconstructions based on autofluorescence show that a thin-walled genital chamber is usually situated in a transverse plane and precisely copies the shape of the spermatophore. A thin vertical longitudinal plate (homologous to female longitudinal bridge) joins the genital chamber and ventral genital cuticle. The anterior genital apodeme is a separate vertical plate situated ahead of the genital chamber and provides a rigid support for it. The brightly autofluorescent ductus ejaculatorius starts from the posterior extremity of the genital chamber and goes backward. Proximally, the ductus ejaculatorius is tube-like, whereas distally, it is expanded into a sac. Confocal laser scanning microscopy observations on males, stained with phalloidin, indicate that the proximal ductus ejaculatorius is devoid of muscles whereas the distal ductus ejaculatorius possesses well-developed musculature (the "spermatophore pump"), appearing in 3D reconstructions as a hollow sphere with three apertures: one anterior and two posterior. Two thin-walled sausage-like vasa deferentia join the distal ductus ejaculatorius with a large single testis, each junction is encircled by a strong, ring-shaped muscle (musculus sphincter testiculodeferentis). Thin muscular fibers of the wall of the testis form a net-like pattern consisting of distinct polygonal cells. The topography of the male internal genitalia and musculature suggests that, contrary to previous observations, the spermatophore head might be extruded first and then the spermatophore stalk appears. The possible role of visceral and skeletal musculature, in the process of the expulsion of a spermatophore, is discussed.

Three-dimensional reconstruction of deferent ducts papillae in urogenital duct system of the male rat

BACKGROUND

The rodent ejaculatory ducts penetrate the male accessory sex gland complex and open into the urethra, anatomically similar to humans. Although the deferent ducts papillae in rodents have been described at the distal end of deferent ducts, they are absent in humans, and their detailed morphology has been unclear.

METHODS

The detailed anatomical structures of the distal end of the deferent ducts of rats were investigated by the computer assisted three-dimensional reconstruction analysis using serial sections of the male accessory sex gland complexes in rats.

RESULTS

The present study revealed that a pair of deferent ducts enters the ventral side of the male accessory sex gland complex, runs caudally parallel to the urethra, and then exits at about midsection of the dorso-lateral lobe of prostate. They are composed of mammilliform papillae, called the deferent duct papillae, which dorso-laterally protrude into the duct lumen from intra-ventral portion of the main duct of ampullary gland. The internal surface of the deferent ducts papillae is composed of ciliated columnar epithelium continuous from the deferent ducts, while their external surface is composed of the columnar secretory epithelium of the ampullary glands. Sphincter muscles were not observed in the deferent ducts papillae, while their lamina propria were occupied by many arterial or venous capillaries.

CONCLUSIONS

The deferent ducts of rat terminated at the deferent ducts papillae that located at the main duct of ampullary glands that drained into the urethra. The deferent ducts papillae might be controlled by the expansion/contraction of well-developed papillary mucosal capillary vessels.

Fishery induces sperm depletion and reduction in male reproductive potential for crab species under male-biased harvest strategy

Sperm depletion in males can occur when polygynous species are intensively exploited under a male-biased management strategy. In fisheries involving crabs species, the effects of this type of management on the reproductive potential is far from being understood. This study tests whether male-biased management of the principal Chilean crab fishery is able to affect the potential capacity of Metacarcinus edwardsii males to transfer sperm to females. Five localities in southern Chile, recording contrasting crab fishery landing, were selected to assess the potential of sperm depletion triggered by fishery. Seasonally, male crabs from each locality were obtained. Dry weight and histological condition of vasa deferentia and the Vaso-Somatic Index (VSI) were determined in order to use them as proxies for sperm depletion and male reproductive condition. A manipulative experiment was performed in the laboratory to estimate vasa deferentia weight and VSI from just-mated males in order to obtain a reference point for the potential effects of the fishery on sperm reserves. Sperm storage capacity is significantly affected by fisheries; during the mating season vasa deferentia from localities with low fishery intensity were heavier than those from high intensity fisheries, and these differences were even more evident in large males. Histological section showed that this disparity in vasa deferentia weight was explained principally by differences in the quantity of spermatophores rather than other seminal material. VSI was always higher in males from localities with low fishery intensity. Males from localities with high fishery intensity showed little capacity to recover sperm reserves and the VSI of these males remained below the values of the just-mated males. Detriment in the capacity of males to transfer sperm is the first step to sperm limitation in an exploited population, thus detection of sperm depletion can be an alert to introduce changes in the current management of crabs.

Vas deferens and penis development in the imposex-exhibiting female rock shell, Thais clavigera

The characteristics of the development of male genitalia (penis and vas deferens) in imposex-exhibiting female rock shells, Thais clavigera, were histologically examined using specimens from a wild population and tributyltin (TBT)-exposed females in the laboratory. A variety of vas deferens morphogenesis patterns were observed in wild female T. clavigera, and the characteristics were summarized. The immature vas deferens at an initial stage, however, was only observed beneath or behind the penis, and no vas deferens was observed close to the vaginal opening (i.e., vulva) of the capsule gland in TBT-exposed females, which was different from the characteristics of vas deferens formation observed in wild females. Taking into consideration both the observed results from wild female specimens and from TBT-exposed females in the laboratory, the vas deferens sequence (VDS) index for T. clavigera was proposed as VDS 1-6.

Application of optical coherence tomography and high-frequency ultrasound imaging during noninvasive laser vasectomy

A noninvasive approach to vasectomy may eliminate male fear of complications related to surgery and increase its acceptance. Noninvasive laser thermal occlusion of the canine vas deferens has recently been reported. Optical coherence tomography (OCT) and high-frequency ultrasound (HFUS) are compared for monitoring laser thermal coagulation of the vas in an acute canine model. Bilateral noninvasive laser coagulation of the vas was performed in six dogs (n=12 vasa) using a Ytterbium fiber laser wavelength of 1075 nm, incident power of 9.0 W, pulse duration of 500 ms, pulse rate of 1 Hz, and 3-mm-diameter spot. Cryogen spray cooling was used to prevent skin burns during the procedure. An OCT system with endoscopic probe and a HFUS system with 20-MHz transducer were used to image the vas immediately before and after the procedure. Vasa were then excised and processed for gross and histologic analysis for comparison with OCT and HFUS images. OCT provided high-resolution, superficial imaging of the compressed vas within the vas ring clamp, while HFUS provided deeper imaging of the vas held manually in the scrotal fold. Both OCT and high HFUS are promising imaging modalities for real-time confirmation of vas occlusion during noninvasive laser vasectomy.

Anatomical and histological equivalence of the human, canine, and bull vas deferens

INTRODUCTION

Several animal models have been utilized for in-vitro experimentation and surgical training exercises of the vas deferens. The canine model is currently the standard for both in-vivo and ex-vivo study. Due to increasing costs associated with experimentation on canines, and in keeping with the principles of refine, reduce, and replace, a novel model that is cost-effective and easily obtained is desired. We compared morphology of the bull vas deferens to that of the human and the canine.

MATERIALS AND METHODS

Bilateral vas deferens tissue from the human (n = 6), canine (n = 6), and bull (n = 5) were compared. Outer diameter (OD), inner diameter (ID), and microscopic measurements of the luminal mucosa and muscularis were then determined from each of these tissues. Histological comparisons were performed by a single pathologist. Data was analyzed using Two One-sided Tests (TOST) Analysis of Equivalence.

RESULTS

According to the TOST statistical analysis, the vassal ID was equivalent for all three species. Similarly, equivalent microscopic measurements were noted for both vassal mucosal (human-canine and human-bull) and muscularis thicknesses (canine-bull). Lastly, all three species had similar histological characteristics.

CONCLUSIONS

The vas deferens' of the human, canine, and bull are equivalent in many ways, including histological similarities. It is reasonable to conclude that the bull vas could be substituted for the human vas for both in-vitro testing and microscopic vasovasostomy simulation exercises. Specimens are cost-effective, provide ample tissue length, and are easy to obtain.

Management of the looping vas deferens during laparoscopic orchiopexy

PURPOSE

A number of variables should be assessed during laparoscopic orchiopexy, including vas anatomy. A looping vas deferens enters the inguinal canal and loops back to the abdominal cavity. This anatomical variant is not uncommonly encountered. Some groups considered this condition in their laparoscopic classification of nonpalpable testis. We present our experience with managing the looping vas during laparoscopic orchiopexy.

MATERIALS AND METHODS

We identified this condition in 18 procedures. In 14 cases it was possible to bring the vas back to the abdominal cavity. In 3 cases the loop could not be brought back laparoscopically and an inguinal incision was used. After the vas was dissected free and dropped into the abdominal cavity pneumoperitoneum was resumed and the procedure was completed laparoscopically. A Web based survey was done to test the value of this method.

RESULTS

A total of 17 procedures were completed successfully with preservation of the vas deferens while in 1 the vas was inadvertently cut. A looping vas did not significantly affect operative time. All 18 testes were viable and retained the scrotal position on followup scrotal Doppler ultrasound.

CONCLUSIONS

Verification of vasal anatomy is a crucial step that should be completed before any dissection. Bringing a looping vas back to the abdominal cavity is usually feasible laparoscopically but in a few cases this may require a small incision to dissect the vasal loop from its inguinal attachments.

Arterial supply of human and bovine testes: a topographic and morphometric comparison study

The aim of the study was to compare the arteries supplying human and bovine masculine gonads. The study was made on two extremely different types of location of the mediastinum testis. The study was made on 100 (50 human and 50 bovine) corrosive casts of the testicular, cremasteric, and deference duct arteries. The differences between the species included different courses of the testicular artery inside the spermatic duct, the relative size of the three arterial diameters, and the morphology of the anastomoses of the arteries. In human testicular arteries, the course inside the spermatic course was more variable than in that of bulls. The artery was straighter and in 80% of the cases did not form the loops which were present in 100% of the bovine specimens. The bovine testicular artery was significantly wider in relation to the cremasteric and deferens duct arteries than the human one. This finding suggests that collateral blood flow to the testis was less effective in bulls than in men. The human testicular artery directly connected the other two with its terminal branches. The bovine testicular artery connected with the cremasteric and deferens duct arteries indirectly by means of its deferens duct branch.

High-resolution sonography of the normal extrapelvic vas deferens

OBJECTIVE

The purpose of this study was to determine the reliability of sonographic visualization of the normal extrapelvic vas deferens and to analyze its appearance and dimensions.

METHODS

Scans of the scrotum and spermatic cords were obtained in 25 fertile volunteers. Identification of the vas deferens was attempted bilaterally in the scrotal, suprascrotal, and prepubic segments in all volunteers. When possible, the total thickness and the diameter of the lumen were measured. Visualization and dimensions were correlated with the body mass index (BMI) and abstinence interval.

RESULTS

All segments of the vas deferens were identified bilaterally in all volunteers. In all cases, it appeared as an anechoic or very hypoechoic tubular structure that was noncompressible and contained no detectable blood flow. It was convoluted inferiorly and became straight as it progressed from the scrotum to the suprascrotal and prepubic segments. The lumen was seen in the suprascrotal segment in all of the volunteers except the one with the highest BMI. The total thickness of the vas ranged from 1.5 to 2.7 mm (mean, 1.89 mm). The lumen of the vas ranged from 0.2 to 0.7 mm (mean, 0.43 mm). There was no correlation between the luminal diameter and the abstinence interval.

CONCLUSIONS

The extrapelvic portion of the vas deferens is reliably visualized sonographically. Its appearance is characteristic and reproducible. The lumen can be measured in almost all cases.

Morphology of male reproductive system in three species of Trypoxylon (Trypargilum) Richards (Hymenoptera: Crabronidae)

Variations in the adult male reproductive system among different groups of Hymenoptera offer characteristics that help studies on behavior and phylogenetics. The objective of this study was to describe the adult male reproductive system of three Trypoxylon (Trypargilum) species. For that, tissues were disseced, fixed in 2.5% glutaraldehyde in 0.1 M sodium cacodylate buffer, pH 7.2 and postfixed in 1% osmium tetroxide. The material was dehydratated and embedded for light and electron transmission microscopes. The species have similar reproductive systems, which are formed by a pair of testes, each one with three fusiforme follicles, from which emerges an efferent duct that later joins forming a deferent duct. The deferent duct opens into an ejaculatory duct. The first half of the deferent duct is enlarged and differentiated in a region specialized in sperm storage, the seminal vesicle. The accessory gland flows in the post-vesicular region of the deferent duct. The testes and vesicles are both covered with a conjunctive capsule. Sexually mature individuals have all spermatogenesis stages in their follicles. Sperms are released from testes in bundles which are disorganized inside seminal vesicles.

Magnetic resonance imaging (MRI) anatomy of the prostate and application of MRI in radiotherapy planning

Radiotherapy planning for prostate carcinoma has traditionally been performed on computed tomography (CT)-images, on which both the high dose areas (prostate with or without seminal vesicles) as well as the low dose areas (surrounding structures, such as the rectum and bladder) are anatomically delineated. However, magnetic resonance imaging (MRI) provides much more information than CT; it can superbly demonstrate the internal prostatic anatomy, prostatic margins and the extent of prostatic tumours. Hence, MRI becomes a powerful tool to improve the accuracy of planning delineations in radiotherapy for prostate carcinoma and is rapidly gaining popularity in the radiotherapy community. The present paper reviews some important anatomical landmarks and acquisition protocols relevant to radiotherapy planning and explains the rationale and importance of close collaboration between radiotherapists and radiologists in optimizing radiotherapy for patients with prostate carcinoma.

Macroscopic Features of the Arterial Supply to the Reproductive System of the Male Ostrich (Struthio camelus)

The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.

Normal and variant appearances of the adult epididymis and vas deferens on high-resolution sonography

PURPOSE

To describe the appearance, anatomic position, and size of the normal adult epididymis and vas deferens using high-resolution sonography.

METHODS

The sonographic appearance, anatomic position, and size of the epididymal head (EH), epididymal body (EB), epididymo-deferential loop (EDL), and vas deferens (VD) were evaluated in 112 consecutive infertile men (infertile group), and the data were compared with those from 84 consecutive men without history of infertility (reference group).

RESULTS

Compared with the testis, the EH was isoechoic, the EB hypoechoic, and the VD anechoic. In 88.4% of cases in the infertile group and 97.6% of cases in the reference group, the EH was located above the upper pole of the testis, with the EB lateral to the testis and the EDL below the lower pole of the testis. In 9% of cases in the infertile group and 6% of cases in the reference group, the EB was located posterior to the body of the testis, with the EDL inverted and the VD anterior to the ET. In 11.6% of cases in the infertile group and 2.4% of cases in the reference group, the epididymis was inverted, with the EH located below the lower pole of the testis. The mean (+/-SD) normal sizes were as follows: EH, 7.6 +/- 1.6 mm; EB, 3.2 +/- 0.8 mm; EDL, 7.7 +/- 1.3 mm; VD, 1.9 +/- 0.2 mm. No statistically significant differences in size were found between the 2 groups.

CONCLUSIONS

We describe the normal and variant appearance, position, and size of the adult epididymis and VD on high-resolution sonography.

The plasminogen activator system modulates sympathetic nerve function

Sympathetic neurons synthesize and release tissue plasminogen activator (t-PA). We investigated whether t-PA modulates sympathetic activity. t-PA inhibition markedly reduced contraction of the guinea pig vas deferens to electrical field stimulation (EFS) and norepinephrine (NE) exocytosis from cardiac synaptosomes. Recombinant t-PA (rt-PA) induced exocytotic and carrier-mediated NE release from cardiac synaptosomes and cultured neuroblastoma cells; this was a plasmin-independent effect but was potentiated by a fibrinogen cleavage product. Notably, hearts from t-PA–null mice released much less NE upon EFS than their wild-type (WT) controls (i.e., a 76.5% decrease; P < 0.01), whereas hearts from plasminogen activator inhibitor-1 (PAI-1)–null mice released much more NE (i.e., a 275% increase; P < 0.05). Furthermore, vasa deferentia from t-PA–null mice were hyporesponsive to EFS (P < 0.0001) but were normalized by the addition of rt-PA. In contrast, vasa from PAI-1–null mice were much more responsive (P < 0.05). Coronary NE overflow from hearts subjected to ischemia/reperfusion was much smaller in t-PA–null than in WT control mice (P < 0.01). Furthermore, reperfusion arrhythmias were significantly reduced (P < 0.05) in t-PA–null hearts. Thus, t-PA enhances NE release from sympathetic nerves and contributes to cardiac arrhythmias in ischemia/reperfusion. Because the risk of arrhythmias and sudden cardiac death is increased in hyperadrenergic conditions, targeting the NE-releasing effect of t-PA may have valuable therapeutic potential.

The Gross Anatomy of the Male Reproductive System of a Neotropical Rodent: the Agouti (Dasyprota leporina)

The literature available on the agouti (Dasyprocta leporina) is very limited. The agouti is a Neotropical rodent found in Trinidad and Tobago, Central and South America. This study focuses on one of the many unexplored areas relating to the species, the male reproductive system. The results showed that the mean testicular length, diameter and weight was 3.67 +/- 0.12 cm, 1.67 +/- 0.04 cm and 5.03 +/- 0.52 g respectively. The paired testes and epididymis were found in contact with the abdominal muscles within scrotal pouches, which are evaginations of the caudoventral abdominal wall. The caput epididymis is enclosed by a fat body. The ductus deferens has a mean length and diameter of 10.98 +/- 0.40 cm and 0.14 +/- 0.01 cm respectively. At the urethral end of the ductus deferens the diameter of each duct expends to form the ampulla. The mean diameter of each of the ampulla was 0.25 cm. The accessory sex organs of the male agouti (D. leporina) include the vesicular glands, the coagulating glands, the prostate glands and the bulbourethral glands. The penis of the agouti is U-shaped with a mean length of 9.90 +/- 0.43 cm. The glans penis contains an os penis, a pair of lateral penile cartilages and paired ventral keratinaceous styles.

[Routing reseach of vas deferens on anatomy and clinical application]

OBJECTIVE

Studying on the routes of vas deferens to provide anatomy basis for surgical operation, especially, reconstruction of long segment loss of vas deferens.

METHODS

The routes of vas deferens were observed and anatomic distances along epididymal, infrainguinal, inguinal, retroperitoneal and ampullar segments of vas deferens, the distances from external ring to extremity of vas deferens were measured respectively in 18 formalin fixed adult cadavers.

RESULTS

The vas deferens have a large curve from external ring to extremity in its route, draw it out from the external ring. Eliminating this curve will allow to shorten this segment of vas deferens for vasovasostomy by 6.1 - 12.9 (9.31 +/- 1.30) cm. The length of each segment of vas deferens, respectively, is epididymal: 3.2 - 5.6 (4.53 +/- 0.79) cm, infrainguinal: 4.5 - 9.5 (7.31 +/- 1.78) cm, inguinal: 4.4 - 7.5 (5.52 +/- 0.74) cm, retroperitoneal: 12.5 - 19.5 (16.75 +/- 1.87) cm and ampullar: 2.9 - 3.8 (3.63 +/- 0.23) cm. There was no significant differences in segment length and the distances from external ring to extremity of vas deferens between the right and left.

CONCLUSION

Reconstruction of long segment loss of vas deferens can be performed by mobilization retroperitoneal vas deferens and draw it out from external ring. There were no significant differences in lengths of vas deferens and the distances from external ring to vassal extremity between the left and right in adults. The surgical operations of vas deferens are closely related each segment of vasa.

Spermatozoa and spermiogenesis of Holocnemus pluchei (Scopoli, 1763) (Pholcidae, Araneae)

Until now, the knowledge on pholcid spermatozoa is based on two species, Pholcus phalangioides and, incompletely, Holocnemus pluchei. To complete this knowledge and to reveal more potential phylogenetic characters, we have investigated sperm ultrastructure and spermiogenesis of H. pluchei. We found that the sperm cells of this species are clearly different from those of P. phalangioides with respect to: (1) the lack of specialization in the cylindrical acrosomal vacuole; (2) a nuclear canal which is located in the periphery and not in the center of the nucleus; (3) a more prominent postcentriolar elongation of the nucleus; (4) the presence of "inner microtubules" in the implantation fossa in early and mid-spermatids; (5) the absence of a helical band of nuclear material; (6) the proximal centriole which is not prolonged; (7) the types of secretion in the seminal fluid (only two types in H. pluchei). Similarities in the spermatozoa of both species concern: (1) a large implantation fossa which contains large amounts of glycogen in mature spermatozoa; (2) absence of a centriolar adjunct; (3) an axonemal basis located in the posterior part of the implantation fossa; (4) the formation of the so-called cleistospermia in the vas deferens. Our results strongly support systematic relationships within Pholcidae placing these two species in different subgroups.

Regional differences in extracellular purine degradation in the prostatic and epididymal portions of the rat vas deferens

1. The aim of the present study was to compare ecto-nucleotidase activities in rat bisected vas deferens using 1,N6-etheno(epsilon)-nucleotides (epsilon-ATP and epsilon-AMP) as substrates. Degradation was estimated by measuring the disappearance of the substrate and the appearance of its metabolites using HPLC with fluorescence detection. Incubation of tissue preparations (prostatic or epididymal portions) with 300 nmol/L epsilon-ATP at 37 degrees C caused a partial disappearance of epsilon-ATP and appearance of its metabolites (epsilon-ADP, epsilon-AMP and epsilon-adenosine). Incubation at 25 degrees C reduced epsilon-ATP degradation more in the prostatic than in the epididymal portion. 2. Incubation of tissue preparations with epsilon-AMP at 37 degrees C resulted in the disappearance of epsilon-AMP and the appearance of epsilon-adenosine, which was more pronounced in the epididymal than in the prostatic portion. Incubation at 25 degrees C reduced epsilon-AMP degradation more in the epididymal than in the prostatic portion. 3. Decreasing pH from 7.4 to 6.5 enhanced epsilon-AMP degradation only in the prostatic portion, whereas increasing pH from 7.4 to 8.5 enhanced epsilon-AMP degradation in both portions, but more markedly in the epididymal portion. The alkaline phosphatase inhibitors levamisole (10 mmol/L) and beta-glycerophosphate (10 mmol/L) reduced epsilon-AMP degradation only in the epididymal portion. 4. In conclusion, the results of the present study are compatible with the presence, in the bisected rat vas deferens, of an ecto-nucleotidase system that is involved in the degradation of extracellular purines, which may differ between the epididymal and prostatic portions, with the epididymal portion presenting a different and higher capacity to form adenosine.

Magnetic resonance imaging anatomy of the prostate and periprostatic area: a guide for radiotherapists

Magnetic resonance imaging (MRI) offers superb soft tissue contrast on T2-weighted images and allows direct multiplanar image acquisition. It can show the internal prostatic anatomy, prostatic margins, and the extent of prostatic tumors in much more detail than computed tomography (CT) images. The present article reviews some key prostatic and periprostatic radiologic landmarks that can be helpful for the radiotherapist using T2-weighted MRI as an adjunct to CT in treatment planning for prostate cancer.

Ultrastructural evidence for secretion from the epithelium of ampulla ductus deferentis of the fan-throated lizardSitana ponticeriana Cuvier

Among reptiles, an ampulla ductus deferentis has been reported only in Squamata. Fairly detailed studies are available only for two species, the lizard Calotes versicolor (Fam: Agamidae) and the snake Seminatrix pygaea (Fam: Colubridae). The light microscopic study on C. versicolor revealed the ampulla to be a prominent organ, whereas the light and transmission electron microscopic study in S. pygaea revealed it to be discernable only in histological preparations. Further, the epithelium of the ductal portion of vas deferens as well as the ampulla of C. versicolor appears to contribute to the seminal plasma and can also phagocytose dead sperm, whereas in S. pygaea neither of these roles has been established. Thus, we hypothesize that there may be variations in the anatomy, histology, and the role of the vas deferens in general, and the ampulla in particular, of the squamate reptiles. In this study, the ductus deferens of the small fan-throated lizard Sitana ponticeriana (Fam: Agamidae) was subjected to light and transmission electron microscopic analysis. In this lizard the ampulla is more prominent than in C. versicolor. The epithelium of the ductal portion of vas deferens consists of principal cells (with features reflecting roles in endocytosis and phagocytosis of dead sperm), dark cells (which are absent in the epithelium of the ductal portion of vas deferens of snakes), and basal cells. The ampulla of S. ponticeriana is differentiated into storage and glandular portions. The epithelium of the storage portion is like that in the ductal portion of the vas deferens, whereas that of the glandular portion, consisting of dark and light principal cells and foamy cells, is tall and forms into smooth villous folds. All three cell types show evidence for a role in secretion, in all likelihood different from each other, for release into the lumen to contribute to seminal plasma. These cells do not provide evidence of a role in phagocytosis of dead sperm. It appears that within the Squamata, the ductal ampulla differs in structure as well as function. We suggest that the ductal ampulla of agamid lizards is a composite gland of the ampulla ductus deferentis and seminal vesicles of mammals.

Renal sexual segment of the ground skink,Scincella laterale (Reptilia, Squamata, Scincidae)

Mature squamates possess hypertrophied regions of the distal urinary ducts, the renal sexual segment (RSS). The RSS is believed to provide seminal fluid that mixes with sperm and is released into the female cloaca during coitus. This study is the first to describe ultrastructure of the RSS in a lizard collected throughout the active season. The species examined, Scincella laterale, represents the largest family (Scincidae: 1,200 species) of lizards. Although sperm are present in the posterior ductus deferens of male S. laterale throughout the year, an annual spermatogenic cycle occurs that results in spermiation in spring, coinciding with maximum development of the RSS. Female S. laterale may possess stored sperm in vaginal crypts from March-May and large oviductal eggs April-June. Thus, the correlation between mating and RSS activity observed in other squamates is also found in S. laterale. Cytologically, the active RSS consists of columnar cells with numerous apical, electron-dense secretory vacuoles which are released by an apocrine process. The granules stain positively for proteins with bromphenol blue and react with PAS for neutral carbohydrates. After the mating season the RSS undergoes recrudescence and the electron-dense granules are replaced by a mucoid secretion that characterizes more proximal portions of the nephric tubules throughout the year. Little variation in ultrastructure of the RSS occurs between S. laterale and Cnemidophorus lemniscatus (Teiidae), the only other lizard in which seasonal variation of the RSS has been studied using similar methods. Females exhibit differentiation similar to that of males in the distal urinary tubules, but to a lesser degree. This is only the second such report for female squamates, and the differentiation of the region in females is proposed to result from adrenal androgens.

Sperm storage in males of the snake Crotalus durissus terrificus (Crotalinae: Viperidae) in southeastern Brazil

Seasonal variations in spermatozoa numbers and in sperm motility along the vas deferens in Crotalus durissus terrificus from southeastern Brazil were analyzed. Our data demonstrate storage and motility of the spermatozoa along the vas deferens throughout the year. This is characteristic of a postnuptial reproductive cycle, usually found in snakes living in temperate climates. We describe similarities in reproductive cycle patterns found in the tropical nonhibernator C. durissus terrificus and in hibernator snakes from temperate zones. Our results show that in C. durissus terrificus, a significant difference in spermatozoa counts occurs between winter and summer. Higher numbers of spermatozoa in summer and autumn, due to intense spermiogenesis, coincides with the mating season in autumn. These data indicate that after spermiogenesis in summer, the males combine the peak of sperm storage to the period females are attractive. Mating, however, is not linked to ovulation, and the sperm is stored in the females during winter until fertilization occurs in spring. In the males, after mating, spermatozoon counts low. In spring, they gradually increase, turning again the highest in summer and autumn. During spermiogenesis in the convoluted vas deferens, spermatozoa gain motility, enhancing their performance along their way towards the distal portion.

Morphology of the male reproductive duct system of Caiman crocodilus (Crocodylia, Alligatoridae)

The male reproductive duct system of Caiman crocodilus in different reproductive stages was studied using light and electron microscopy, to determine whether shared morphological features exist between Crocodylia and Aves, in concurrence with the Archosauria hypothesis. The sexual duct system of Caiman crocodilus is constituted of the rete testis, ductuli efferentes, ductuli epididymides, ductus epididymidis, and ductus deferens. The morphology and histochemical properties of these ducts suggest their involvement in seminal fluid production and/or its modification. Three types of non-ciliated cells were identified along the duct system. 1. The noncliated cells of the ductuli efferentes contain electron dense worm-like structures and coated vesicles, both related to absorptive processes, as has been suggested in Aves. 2. The non-ciliated cells of the ductuli epididymides have apical electron dense granules suggesting a secretory role, and 3. The non-ciliated cells of the ductus epididymidis and ductus deferens did not exhibit conspicuous storage of secretory material, but have a prominent rough endoplasmic reticulum content indicating active protein production. The occurrence of abundant secretory granules in the epithelial cells of the distal ductus deferens during non-reproductive stages suggests its participation in the removal of luminal debris when the reproductive season ends. Additional ducts were observed running along the ductus deferens; they shared morphological characteristics with the ductuli epididymides. The maximum diameter and therefore the greatest sperm accumulation of the excurrent ducts were observed during the initial testicular regression. The comparative analysis suggests that the male reproductive system of the Crocodylia exhibits structural characteristics nearer to those of Aves than to Lepidosauria, Testudines, and Mammalia, additional data that support an Aves and Crocodylia sister group relationship.

Mechanisms of parasite-induced sex reversal in Gammarus duebeni

The amphipod Gammarus duebeni is host to the feminising microsporidian parasite Nosema granulosis that converts males into functional females. To test the hypothesis that the parasite acts through endocrine disruption we compared the morphology of the gonad and activity of the androgenic gland, which coordinates male sexual differentiation, in infected and uninfected animals. Male gonad consisted of testis, seminal vesicle and vas deferens that was anchored to the genital papilla on segment 7. The androgenic gland was associated with the distal end of the vas deferens. In female and intersex animals the bi-lobed ovary opened into the oviduct at segment 5, vestigial vas deferens and vestigial androgenic gland were retained. The majority of parasitised individuals (38/39) were either phenotypic females or intersexes with fully developed ovaries and an undifferentiated androgenic gland. Our data suggest that the parasite prevents differentiation of the androgenic gland. In further support of this hypothesis, mass spectrometry of a single androgenic gland from males revealed a dominant molecular ion with a mass/charge ratio of 4818.4+H, corresponding to a peptide of androgenic gland hormone from Armadillidium vulgare. In contrast the vestigial androgenic gland from parasitised and unparasitised females showed only low intensity peaks. Our observations demonstrate that the parasite manipulates host sex by preventing androgenic gland differentiation, androgenic gland hormone production and consequently male differentiation. This is in agreement with observations of A. vulgare with inherited Wolbachia infection, suggesting that phylogenetically distant feminisers manipulate hosts through a common mechanism. The high frequency of infection in intersexes (89.3%) suggests that this phenotype results from incomplete feminisation by the parasite.

Antispermatogenic and hormonal effects of Crotalaria juncea Linn. seed extracts in male mice

AIM

To evaluate the antifertility activity of various extracts of Crotalaria juncea seeds in male mice.

METHODS

Adult male mice were gavaged the petroleum ether, benzene and ethanol extracts of C. juncea seeds, 25 mg x (100g)(-1) x day(-1) for 30 days. On day 31 the animals were sacrificed by cervical dislocation and the testes, epididymis, vas deferens, seminal vesicles, prostate gland, bulbourethral gland and levator ani were dissected out and weighed. The organs were processed for biochemical and histological examination.

RESULTS

In petroleum ether, benzene and ethanol extracts treated rats, there was a decrease in the weights of testis and accessory reproductive organs. The diameters of the testis and seminiferous tubules were decreased. Spermatogonia, spermatocytes and spermatids in the testis and the sperm count in cauda epididymis were also decreased. There was a significant reduction in the protein and glycogen contents and an increase in the cholesterol content in the testis, epididymis and vas deferens. Of the 3 extracts, the ethanol extract appeared to be the most potent in antispermatogenic activity. When the ethanol extract was tested in immature male mice, there was an antiandrogenic effect as the weights of accessory organs were reduced.

CONCLUSION

The various extracts of C. juncea seeds arrest spermatogenesis and are likely to have an antiandrogenic activity.

Histological study of vas deferens following intravasal laser irradiation

AIM

To study the histologic changes of the vas deferens following Nd: YAG laser irradiation.

METHODS

Intravasal laser irradiation was given to (i) 52 segments of rabbit (laser dosage: 2 seconds at 40 W approximately 50 W) and 16 segments of human (3 seconds at 45 W approximately 55 W) vas deferens in vitro, (ii) 25 rabbit vasa (2 seconds approximately 2.5 seconds at 40 W approximately 45 W) in vivo and (iii) 2 human vasa (3 seconds at 55 W) in vivo. Segments of vasa were removed from the in vivo irradiated vasa deferentia 15 days approximately 180 days (rabbit) or 15 days (man) after the exposure. All vas segments were embedded in methacrylate resin. Serial sections (thickness 25 microm approximately 30 microm) were obtained and observed under a light microscope.

RESULTS

(i) Laser-induced damage reached the muscularis layer in 27% and 94% of the rabbit and human vas segments in vitro, respectively. (ii) Fourteen of the 25 in vivo rabbit vasa were completely occluded by fibrous tissue and the longer the time interval after treatment, the more likely was the vas occluded. Those unoccluded vasa had either a normal histology or a mucosal damage. (iii) One in vivo human vas was almost completely occluded by the fibrous tissue but the other had a relatively large lumen packed with sperm granulomatous tissue and partial destruction of the smooth muscle layer.

CONCLUSION

Laser irradiation can induce long-term vas occlusion; for rapid occlusion, laser doses just completely destroying the mucosal layer will be advisable.

The effects of paroxetine on rat isolated vas deferens

The aim of the present study is to evaluate whether paroxetine (a selective serotonin re-uptake inhibitor) can modify the contractile responses of isolated vas deferens. Some contractile agents, potassium chloride (KCl), adenosine 5'-triphosphate (ATP), noradrenaline (NA), and electrical field stimulation (EFS) caused contractions both in epididymal and prostatic portions of vas deferens. Paroxetine (PX) in concentrations 10(-7) and 10(-6)M potentiated the contractions to KCl and ATP only in epididymal portion but in higher concentrations (10(-5) and 10(-4)M) inhibited the responses in both portions. NA responses were inhibited by PX in all concentrations used, both in prostatic and epididymal portions. Prazosin (PR), an alpha adrenergic receptor blocking agent, inhibited PX-induced potentiation observed for higher concentrations of KCl. PR also inhibited PX-induced potentiation on the responses to ATP in epididymal portion. Pretreatment with PX (10(-7) to 10(-6)M) increased the contractions to EFS but in 10(-5) and 10(-4)M concentrations inhibited them. Even though the preparations were washed out, the inhibited responses of contractile agents could not be restored. After a washout period for PX, when Bay K 8644 (calcium channel activator) was added to the bath medium, the contractile responses to KCl were partially restored. In calcium-free medium, KCl caused contractions in concentrations higher than 80 mM with lower amplitudes which were not affected by PX. Reserpinization did not change the inhibitory pattern of PX's effect on exogenously applied NA in all concentrations tested. In reserpinized rats, the potentiation caused by PX in exogenously applied ATP responses was not observed. In conclusion, we can say that PX has two different effects: inhibition and potentiation of contractions to various agonists. The inhibitory effect of the drug can be explained by a calcium channel blocking activity. The potentiating effect of the drug is mainly related to its presynaptic action, such as NA re-uptake inhibitory effect.

Structure of the pelvic and penile urethra--relationship with the ducts of the sex accessory glands of the Mongolian gerbil (Meriones unguiculatus)

The urethra is the main place of entry for sexually transmitted pathogens. However, there is little literature on the morphology of the urogenital system, principally the urethra and ducts of the sex accessory glands. The Mongolian gerbil is an insectivorous, herbivorous and monogamous rodent with nocturnal habits; it has been used successfully as a laboratory animal since the 1960s. Therefore, the objective of the present paper was to describe the structure and ultrastructure of the urethra and its relations to the ducts of the accessory sex glands of the Mongolian gerbil (Meriones unguiculatus), contributing to the understanding of the reproductive biology of the rodent and aiming to provide data for future experimental studies. Conventional techniques of light and scanning electron microscopy were utilized. The urethra and ducts of the accessory sex glands are similar to those of the albino rat and the mouse. However, there is variation in drainage type among accessory sex glands for the inner urethra. The ducts of the seminal vesicle, the ductus deferens, drain their contents independently into the ampullary duct that opens in the urethra. The ducts of the prostate, coagulating and bulbourethral glands drain their contents independently into the urethra.

Studies on sperm storage in the vas deferens of the spinifex hopping mouse (Notomys alexis)

The cauda epididymidis, with its relatively cool temperature (32-35 degrees C), is considered to be the main site of sperm storage in male mammals. However, in the adult male spinifex hopping mouse, Notomys alexis, similar numbers of spermatozoa are found in the vas deferens to those in the cauda epididymidis. The present study shows that, unlike in the laboratory mouse in which spermatozoa of the vas deferens are found mainly in the epididymal region of the duct, spermatozoa in the hopping mouse are localized mainly to the middle and urethral regions of the vas deferens which lies in the inguinal and lower abdominal region of the body cavity. After ligation of the vas deferens close to its connection with the epididymis, many spermatozoa in the vas deferens retain the potential for motility for up to 2 weeks, indicating that the viability of spermatozoa is not compromised by being restricted to core body temperature. This urethral region of the vas deferens, in which spermatozoa reside, has a highly divergent structural organization compared with that of common laboratory rodents in which there is an expanded lumen with a network of epithelial folds. Ultrastructural observations of the cells lining the duct indicate that there are not any marked differences in morphology compared with the cells lining the duct in common laboratory murids, but the infoldings of the vas deferens of the hopping mouse are highly vascular which might facilitate supply of oxygen and nutrients to the spermatozoa residing in the lumen.

Circadian rhythm of glycoprotein secretion in the vas deferens of the moth, Spodoptera littoralis

BACKGROUND

Reproductive systems of male moths contain circadian clocks, which time the release of sperm bundles from the testis to the upper vas deferens (UVD) and their subsequent transfer from the UVD to the seminal vesicles. Sperm bundles are released from the testis in the evening and are retained in the vas deferens lumen overnight before being transferred to the seminal vesicles. The biological significance of periodic sperm retention in the UVD lumen is not understood. In this study we asked whether there are circadian rhythms in the UVD that are correlated with sperm retention.

RESULTS

We investigated the carbohydrate-rich material present in the UVD wall and lumen during the daily cycle of sperm release using the periodic acid-Shiff reaction (PAS). Males raised in 16:8 light-dark cycles (LD) showed a clear rhythm in the levels of PAS-positive granules in the apical portion of the UVD epithelium. The peak of granule accumulation occurred in the middle of the night and coincided with the maximum presence of sperm bundles in the UVD lumen. These rhythms persisted in constant darkness (DD), indicating that they have circadian nature. They were abolished, however, in constant light (LL) resulting in random patterns of PAS-positive material in the UVD wall. Gel-separation of the UVD homogenates from LD moths followed by detection of carbohydrates on blots revealed daily rhythms in the abundance of specific glycoproteins in the wall and lumen of the UVD.

CONCLUSION

Secretory activity of the vas deferens epithelium is regulated by the circadian clock. Daily rhythms in accumulation and secretion of several glycoproteins are co-ordinated with periodic retention of sperm in the vas deferens lumen.

Spermatophore transfer in the hermit crab Clibanarius vittatus (Crustacea, Anomura, Diogenidae)

Although mating has been described in several hermit crab species, the mechanics of spermatophore transfer have not previously been demonstrated. Evidence from pleopod and gonopore morphology, video observations, and inseminated females indicates that in Clibanarius vittatus the male applies a spermatophoric mass directly onto the female via the gonopores rather than with modified pleopods 1-2 (gonopods) and/or genital papillae as in many other decapods. The single second pleopod of males of C. vittatus has a simple endopod with no apparent modifications for sperm transfer. There are no genital papillae extending from the male gonopores. The globular spermatophores are aligned in rows surrounded by a seminal secretion in the male ducts (vasa deferentia that terminate in ejaculatory ducts opening to the exterior via the gonopores). During copulation, described from time-lapse video recordings, the ventral surface of the last thoracic segment of the male, bearing the gonopores, was apposed to the ventral cephalothorax of the female. A massive amount of seminal secretion containing spermatophore ribbons, termed here the spermatophoric mass and described for the first time in a hermit crab species, was observed covering the sternites and coxae of pereopods 1-5 of a recently copulated female. It is suggested that during copulation the male emits the contents of the ejaculatory ducts directly onto the female without the aid of gonopods or genital papillae. Although spermatophore transfer is simple in C. vittatus, the presence of modified anterior pleopods or elongate genital papillae (sexual tubes) in other paguroidean species suggests the possibility of a more complex insemination process in these other hermit crabs.

The paratesticular region: histoanatomic and general considerations

The paratesticular region includes the testicular collecting system, the testicular tunics, and spermatic cord. For the purpose of discussion in this issue, the rete testis is also considered part of the paratestis, although it is principally intratesticular in location. The embryologic origins of the paratesticular components and their detailed anatomic and histologic features are presented to provide a background to better understand the pathologic processes affecting the paratestis. A wide variety of cysts, hyperplasias, neoplasms, and tumor-like conditions may affect the paratesticular region, at times resulting in challenging problems in differential diagnosis. An approach to the paratesticular causes of an intrascrotal mass lesion is presented.

Immunohistochemical localization of taurine in the male reproductive organs of the rat

The amino acid taurine has been implicated in several aspects of reproductive system physiology. However, its localization in these organs has not been previously analyzed. The aim of this study was to characterize its distribution in male rat reproductive organs by immunohistochemical methods. Taurine was localized in the smooth muscle cells of the tissues studied and in the skeletal fibers of the cremaster muscle. In the testis, taurine was found in Leydig cells, vascular endothelial cells, and other interstitial cells. No immunoreactivity was observed in the cells of the seminiferous tubules, either in germ cells at all spermatogenic stages or in Sertoli cells. However, peritubular myoid cells were immunostained. Most epithelial cells of the efferent ducts were immunolabeled, whereas the epithelial cells of the rete testis (extratesticular segments), epididymis (caput, corpus, and cauda regions), and ductus deferens were unstained. However, most epithelial cells from the intratesticular segments of the rete were immunopositive. Some cells identified as intraepithelial macrophages and lymphocytes, apical cells, and narrow cells were intensely immunolabeled. Regional differences in the distribution of these cell types along the ducts studied were also noted. The possible functional roles for taurine in these cells are discussed.

Repeated vas occlusion and non-invasive reversal with styrene maleic anhydride for male contraception in langur monkeys

The feasibility of a spacing method for contraception, using Styrene Maleic Anhydride (SMA) as a vas occlusive agent, has been assessed in male langur monkeys. The vas deferens of 6 animals were occluded with 60 mg SMA in 120 microL DMSO. After 150 days, the occlusion was reversed by a technique which involved palpation, percutaneous electrical stimulation, forced vibratory movement, suprapubic percussion and per-rectal digital massage of the vas segments. The vas deferens were then re-occluded with SMA and reversed by the non-invasive method after three consecutive azoospermic samples. The second vas occlusion resulted in uniform azoospermia after the third ejaculation and reversal caused the reappearance of spermatozoa in the semen to severe oligozoospermic levels in the first two ejaculations and rising to normospermia in the subsequent ejaculations. Ultrastructure of the spermatozoa by SEM and TEM and sperm function tests revealed that the spermatozoa had recovered normal morphology. Vas morphology also regained a normal pseudostratified columnar epithelium containing basal and principal cells. The results suggest that the SMA-based spacing technique for male contraception could be extrapolated to the human by use of no-scalpel injection and non-invasive reversal.

Reproductive features of the eastern mole (Scalopus aquaticus) and star-nose mole (Condylura cristata)

Since moles are closely related to shrews, the gametes and reproductive tracts of the star-nose mole (Condylura cristata) and the eastern mole (Scalopus aquaticus) were examined to gain further insight into unusual reproductive traits of the Soricidae. Moles display many of these soricid traits, but with some important differences. The cumulus oophorus of Scalopus, ovulated about 16 h after hCG injection, was largely dispersed by hyaluronidase and, though quite dense, was nevertheless more similar to that of higher mammals than to the compact 'ball of the soricid cumulus. Within the female tract in these moles, approximately 85% of the length of the oviduct comprises a narrow ampulla with numerous differentiated crypts that, in shrews, house spermatozoa. However, in contrast to shrews, moles produce considerably larger numbers of spermatozoa, which challenges the proposal that, in shrews, oviductal sperm crypts specifically permit lower sperm production by the males. In the sperm head of these two moles, the acrosome displays the long rostrum that is typical of other Insectivora, and the perforatorium has the barbs by which soricid spermatozoa probably bind to the zona pellucida. Perhaps allied to this, immunoblots indicated that the immunoreactive acrosomal matrix of Scalopus spermatozoa is simpler than the polypeptide complex of the bovine and hamster acrosomal matrix.

The development of male reproductive organ abnormalities after neonatal exposure to tamoxifen is genetically determined

Responses of the male reproductive organs to neonatal exposures of tamoxifen (Tx) were examined in seven different strains of mice (A/J, AKR/J, BALB/cAnN, C3H/HeJ, C57BL/6J, DBA/ 2J, and FVB/N). Male mice were given daily subcutaneous injections of 2 microg Tx from postnatal day 1 to 5, and the testes, epididymides, ductus deferens, and seminal vesicles were examined at 3 months of age. At necropsy, the testes and seminal vesicles of Tx-treated groups were significantly smaller in size than those of the control groups in all strains. Histologically, the testes of AKR/J, BALB/cAnN, and FVB/N mice showed no abnormality after neonatal treatment with Tx. In contrast, the testes of A/J, C3H/HeJ, C57BL/6J, and DBA/ 2J mice were often necrotic and highly disorganized, with severe inflammation. In the connective tissue surrounding these testes, relatively large arteries were involved in the inflammation, and the vascular lumen was occluded by the thickened tunica interna, suggesting that these testicular changes were due to infarction. Similarly, the epididymides and ductus deferens of Tx-treated A/J, C3H/HeJ, C57BL/6J, DBA/2J, and FVB/N mice showed chronic pyogranulomatous inflammation. The epithelium of the seminal vesicles of Tx-treated A/J, C3H/HeJ, C57BU6J, DBA/2J, and FVB/N mice also exhibited moderate hyperplasia, with squamous metaplasia. These results indicate that neonatal exposure to Tx causes various abnormalities of the male reproductive organs in postpubertal mice, depending on the strains, and suggest that a genetic component plays a major role in determining the phenotypic variation observed.

[Effect of cocaine on the contractile response to noradrenaline in the epididymal and prostatic regions of the vas deferens]

In the prostatic half of the rat vas deferens, the response to noradrenaline under the cocaine effect revealed a phasic and a tonic components, whereas in the epididymal portion of the vas deferens there only occurred the tonic component. Cocaine increased the maximal tonic contractile response to noradrenaline in the epididymal portion and the maximal phasic response--in the prostatic one. Mechanisms of direct postsynaptic action of cocaine are discussed.

Microsurgical epididymovasostomy in the rat: comparison of end-to-side and two invagination techniques

Most cases of obstructive azoospermia are caused by epididymal obstruction for which the classical treatment is epididymovasostomy (EVST). We have compared the widely used end-to-side, invaginated end-to-side and invaginated end-to-end operations. Ninety microsurgical two-layer EVST were carried out on rats. The technical advantages were assessed and patency of anastomoses and conception rate, the length of the operation and amount of suture material used measured in each group. There were no significant differences in patencies and conception rate between the three groups. The invagination techniques took significantly less time than the more usual end-to-side operation, and less suture material was used. The invagination techniques are easier to learn, simpler to perform and involve less manipulation, reduce trauma and cause less laceration to the ductus deferens and epididymal tubules. Economically considered, the operations save the expenditure of both time and suture material. Of paramount importance in making the choice is the size of the ductus deferens and that of the epididymal tubules.

Quantification of organotin compounds and determination of imposex in populations of dogwhelks (Nucella lapillus) from Norway

Unintentional effects of the antifouling agent tributyltin (TBT) have been discovered in marine gastropods as the induction of male sex characters in females, known as imposex. The occurrence of imposex in dogwhelks (Nucella lapillus) was investigated in 41 populations sampled in 1993-1995 along the Norwegian coast. A method for quantification of organotin species using gas chromatography and atomic emission detection (GC-AED) was developed. Some degree of imposex occurred in almost all populations of dogwhelks studied, except in four from Northern Norway. The concentration of organotin compounds in the gastropods from the unaffected populations was below the detection limit (7 ng Sn/g d.w.). The concentration of TBT in dogwhelks from affected populations was in the range 48-1096 ng Sn/g d.w. A positive relation between the concentration of TBT in dogwhelks and the degree of imposex was found.

Light microscopic observations on the reproductive tract of the male sand rat, Psammomys obesus

The anatomy of the reproductive tract of the male sand rat, Psammomys obesus, was examined by light microscopy. Histologically, the reproductive tract is similar to other rodent species. Seminiferous tubules in the 1-month-old sand rat do not contain a tubular lumen but Sertoli cells, spermatogonia and spermatocytes are present. A full complement of germ cells is present in the seminiferous tubules by 2.5 months and spermatogenesis is well established. The interstitial space is not well defined until 2.5 months when cell types typical of most rodent species are observed. The epididymis is not noticeably segmented into lobules. An epididymal lumen is not observed until 2.5 months. Cauda epididymal sperm are not observed in the 1 or 2.5-month-old animals and cauda epididymal sperm counts from the 7.5 and 12.5-month-old animals are highly variable. The epididymis, proximal and middle regions of the vas deferens, seminal vesicles and prostate display morphological and histological characteristics similar to other rodent species. The distal end of the vas deferens is not expanded to form an ampulla.

Reversibility with sodium bicarbonate of styrene maleic anhydride, an intravasal injectable contraceptive, in male rats

A copolymer of styrene and maleic anhydride (SMA) was dissolved in dimethyl sulphoxide (DMSO) and injected into the lumen of the vas deferens of rats. The polymer was retained in the lumen for a period of more than 90 days. Sodium bicarbonate (10%), pH 8.9, was used to flush the polymeric material from the vas deferens lumen. The reversibility and patency of the vas deferens was thus obtained. Sodium bicarbonate proved to be an effective alternative to dimethyl sulphoxide for reversal.

Spinal cord segments controlling the canine vas deferens and differentiation of the primate sympathetic pathways to the vas deferens

This study was undertaken to explore the spinal cord segments controlling the canine and human vas deferens and differentiation of the mammalian sympathetic pathways to the vas deferens. Thoracolumbar white communicating rami (WCR) were electrically stimulated in the dogs. Stimulation of the 1st, 2nd, 3rd, and 4th lumbar WCR elicited an elevation of intraluminal pressure of the vas deferens in 2, 10, 16, and 14 of 20 dogs examined, respectively, whereas stimulation of sympathetic chain (between the 13th thoracic and 1st lumbar ganglia), 13th thoracic WCR, intermesenteric plexus, and 5th lumbar WCR showed no response in any of the 10, 2, 12, and 5 dogs examined, respectively. Anatomical study of the 118 human lumbar splanchnic nerves of 55 cadavers showed that almost all lumbar splanchnic nerves (96%) originated from L2 and/or L3 sympathetic chain ganglia (L1-2 spinal cord levels). Comparative anatomical study of the mammalian sympathetic pathways to the vas deferens showed that the caudal mesenteric plexus is not divided in rats, rabbits, cats, and dogs and is partially divided into two plexuses in monkeys and completely in humans and that separation of the sympathetic component in the pelvic nerve (isolation of the sacral splanchnic nerve) is in progress in the primate. These results indicate that spinal cord segments controlling the vas deferens are L1-4 in the dog and probably L1-2 in humans and that differentiation of the sympathetic nerve pathways is proceeding at both main and compensatory pathways to the vas deferens in the primate.

Structure and autonomic innervation of the human vas deferens: a review

The motor innervation of the smooth muscle coat of the human vas deferens is predominantly noradrenergic in type while a less dense and differently distributed presumptive cholinergic innervation is also in evidence, although the precise role of the latter is undetermined. Immunohistochemical studies have confirmed the presence of catecholamine-synthesizing enzymes tyrosine hydroxylase (TH) and dopamine beta hydroxylase (DbetaH) in the majority of fine, varicose intramuscular nerves, about two-thirds of which also contain neuropeptide Y (NPY). Minor populations of noradrenergic nerves contain enkephalin (ENK), galanin (GAL), somatostatin (SOM), or nitric oxide synthase (NOS). The presumptive cholinergic intramuscular nerves contain vasoactive intestinal polypeptide (VIP) and NPY. The subepithelial nerves of the vas deferens are assumed to have a secretomotor function and are rich in acetylcholinesterase and NPY, many also containing either VIP or NOS. The muscle coat of the human vas deferens is poorly differentiated until after birth, the intramuscular nerves in the fetus being relatively thick and non-varicose. Development of a subepithelial nerve plexus lags behind that in the muscle coat but its density in the neonatal vas deferens resembles that seen in the adult. Observations on specimens of human vas deferens obtained at vasovasostomy carried out 1 to 15 years after vasectomy have shown a marked reduction in the density of noradrenergic nerves in the muscle coat of the testicular portion while that in the urethral portion remains unaltered. Furthermore, the subepithelial secretomotor nerves degenerate in the testicular portion. These long-term changes in the pattern of innervation of the vas deferens consequent upon vasectomy may have profound effects upon the outcome of vasovasostomy with respect to subsequent sperm maturation, transport, and viability.

Computer-assisted visualization of the rat epididymis: a methodological study based on paraffin sections autometallographically stained for zinc ions

A concept for the computer-assisted visualization of tubular organs is presented. Unmarked histological zinc-stained serial sections from the epididymis of the Wistar rat were aligned to demonstrate the concept. Virtual images were made through the aligned sections and served as controls for the alignment process. Animation of the serial sections and the virtual images revealed new information about the structure of the organ under investigation. The analysis was used to upgrade the anatomical knowledge of rat epididymis by describing how the epididymal duct runs through the structure. The proximal parts of the epididymis contain large communicating septa of connective tissue dividing the caput and the upper part of the corpus epididymidis into segments. The tortuousness was high in the caput with many turns within a small area of the epididymis, whereas longer loops were found in the lower part of the corpus and cauda epididymidis. The tube of the vas deferens was found to become an integrated part of the ductal system in the cauda epididymidis, although it was histologically easy to distinguish from the epididymal duct. The total number of cross-sections of the ductus epididymidis in the 2254, 15-microm-thick, tissue sections analysed was 104700, giving a minimum length of the ductal system of 1.5 m.