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Query: UNIPROT:Q9UIJ5 (
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Since conventional chemical fixation may extract tissue components and thus alter structural organization, cryofixation was used to reexamine the ultrastructure of three thick basement membranes: lens capsule, Reichert's membrane, and Engelbreth-Holm-Swarm (EHS) tumor matrix, and two thin basement membranes, those of
epididymis
and semi-niferous tubules. Cryofixation was achieved by slam freezing followed by either freeze substitution in dry acetone containing 1% osmium tetroxide and 0.05% uranyl acetate or freeze drying in a molecular distillation dryer. The results by both procedures demonstrate that thick basement membranes and the lamina densa of thin basement membranes are composed of a network of anastomosing strands referred to as cords. The cords vary in density and distinctiveness, but their thickness averages 3 to 5 nm in every tissue examined. The spaces separating the cords vary within wide limits, but their mean diameter is approximately 15 nm in every case. Two other common features are 1) the presence within the network of a few 1.5-3.0-nm-thick filaments and 2) 4.5-nm-wide sets of parallel lines referred to as double tracks. When these results are compared with those previously described after conventional fixation, no significant difference is observed in either the cord network or the associated filaments and "double tracks." However, in the thin basement membranes processed by cryofixation, the lamina densa is in direct contact with epithelial cells, whereas, after conventional fixation, the lamina densa is separated from the epithelial cells by a pale layer referred to as lamina lucida or lamina rara. Immunogold labeling of three basement membranes after cryofixation and freeze substitution in acetone containing 0.3% glutaraldehyde yields strong reactions for laminin, type IV collagen, and heparan sulfate proteoglycan. Comparison with previous results indicates that conventional formaldehyde fixation adequately preserves laminin and type IV collagen but causes the loss of some proteoglycan. It is concluded that, except for this loss and the absence of lamina lucida in cryofixed thin basement membranes, the morphological and antigenic features obtained after cryofixation are similar to those observed in the past after conventional fixation.
Anat
Rec
1993 Feb
PMID:Cryofixation of basement membranes followed by freeze substitution or freeze drying demonstrates that they are composed of a tridimensional network of irregular cords. 842 Mar 89
A morphometric analysis of mouse sperm and of their nuclei was undertaken to investigate their respective post-testicular maturation. Sperm were collected from the testis, caput and cauda epididymidis, and their corresponding nuclei were isolated. Results indicate that the post-testicular maturation of sperm is distinct from that of nuclei. The size of intact sperm heads increases in the caput followed by a subsequent decrease in the cauda. In contrast, sperm nuclei decrease progressively in size. In general, a greater magnitude and number of alterations in intact heads and nuclei occur while in transit from the testis to the caput than during passage to the cauda
epididymis
. These results suggest that the period immediately following their release from the testis is crucial to the complete morphological maturation of sperm heads and nuclei.
Anat
Rec
1993 Apr
PMID:Morphometric analysis of intact sperm heads and of sperm nuclei in the mouse. 846 87
The semen quality, plasma testosterone concentrations and ultrasonographic changes were studied for up to 20 weeks after the unilateral vasectomy of two adult goats and two rams, and the gross and histological changes were examined post mortem. An intact ram and an intact goat served as controls. There was a marked decrease in the sperm concentration and the total numbers of sperm per ejaculate in both species. However, there seemed to be no effect on ejaculatory volume, mass motility and individual motile sperm, percentages of dead and abnormal sperm and plasma concentrations of testosterone. Ultrasonographically, the epididymal tail lost its characteristic heterogeneous texture and appeared enlarged. Anechoic masses, representing sperm granulomata, were visible within the epididymal tail of both the rams, and the epididymal head of one of the goats and at the cut end of the vas deferens in the other. They were observed as early as four to six weeks after surgery and their nature was confirmed post mortem. The sequential ultrasonographic changes in the testis and the
epididymis
are described.
Vet
Rec
1995 Jul 29
PMID:A clinical and ultrasonographic study of the testes and related structures of goats and rams after unilateral vasectomy. 853 54
The development of the testes was studied in rats following prepubertal obstruction of the
epididymis
. Male rats received bilateral ligation of the corpus epididymidis or a sham operation at 10 days of age, and temporal changes in testicular morphology and weights of reproductive organs were determined at intervals spanning sexual maturation. Development of the testes was normal through 35 days of age. The initial histological changes in the testes of ligated animals, observed at 56 days, included an increased diameter of the seminiferous tubule lumen, depletion of spermatids, and the presence of multinucleate spermatids. Subsequently, germ cells were greatly depleted in the testes of 91- and 128-day-old rats with ligated epididymides. After puberty, testicular weight and volume declined relative to corresponding sham-operated animals. On the other hand, the weights of the epididymides in ligated animals prior to puberty significantly exceeded those of sham-operated rats but weighed significantly less than those of rats in the sham group after sexual maturation. Testicular alterations occurred after increases in the weights of the epididymides. Testicular changes may have contributed to rather than resulted from an autoimmune response to spermatozoa because testicular alterations preceded increases in antisperm autoantibodies.
Anat
Rec
1999 01
PMID:Degeneration of the seminiferous epithelium following epididymal obstruction in prepubertal rats. 989 20
Observations from extratesticular rete-ligated, mature goats indicated that epithelial morphology in the tail of the
epididymis
can be maintained without any input from testicular fluid (Goyal et al., Acta Anat., 1994;150: 127-135). Hence, the objective of this study was to determine whether the tail of the
epididymis
and/or other regions of the male excurrent ducts can differentiate prior to the appearance of lumen in the seminiferous tubules, which is an indicator for the onset of seminiferous tubular fluid secretion. Based on age and scrotal circumference (SC), 20 male goats were divided into four groups of five animals each: 1-4 weeks (SC, 6.5-7.5 cm), 7-10 weeks (SC, 8.5-11.0 cm), 12-15 weeks (SC, 11.0-14.0 cm), and 15-25 weeks (SC, 16.0-19.0 cm). Tissues were collected from the testis, six regions of the
epididymis
(proximal, middle and distal head; proximal and distal body; and tail), and the ductus deferens, and were processed for light and electron microscopic examination. Changes in epithelial height and cytological features associated with absorption (microvilli, pinocytotic and coated vesicles) and protein secretion (RER, Golgi body) were used as markers for differentiation. Differentiation of all of these features was comparable to that observed in the 15-25-week-old animals in the ductus deferens by > or = 1 week, in the tail of the
epididymis
by > or = 7 weeks, in the distal body of the
epididymis
by > or = 12 weeks, and in the proximal body of the
epididymis
and all three regions of the head of the
epididymis
by > or = 15 weeks. Seminiferous tubules developed lumens between 12 and 15 weeks. In conclusion, epithelial differentiation in the ductus deferens, tail of the
epididymis
, and distal body of the
epididymis
follows a time-dependent, spatial, ascending order and is achieved before lumen formation in the seminiferous tubules. Conversely, epithelial differentiation in all three regions of the head and the proximal body of the
epididymis
occurs simultaneously and after lumen formation in the seminiferous tubules.
Anat
Rec
1999 04 01
PMID:Postnatal differentiation of the ductus deferens, tail of the epididymis, and distal body of the epididymis in goats occurs independently of rete testis fluid. 1020 58
Reproductive ability is decreased in aged animals and in men. Little is known about the changes taking place in the
epididymis
, and the possible influence on the loss of sperm quality. We studied the age-related alterations in the
epididymis
and in epididymal spermatozoa of hamsters. Adult (6-month-old), middle-aged (18-month-old), and aged (24-month-old) hamsters were used. Serum samples were obtained to determine testosterone levels. Testes and epididymides were removed and studied by light and electron microscopy. Epididymal sperm was also obtained and the motility, position of cytoplasmic droplet, and concentration were evaluated. Measurements of the height of the epithelium, length of stereocilia, external tubular diameter, and thickness of the muscular wall were performed. The proliferative activity was also studied. An ANOVA analysis was used to compare quantitative differences between epididymal zones and age groups. Aged hamsters presented involutive changes in the
epididymis
. A decrease in tubular diameter was found in cauda; principal cell ultrastructure showed changes including the appearance of damaged mitochondria, bundles of filaments, and the accumulation of lipofuscin. Some clear cells showed an unusual morphology by the presence of large electrondense vacuoles. A reduction in sperm quality was also observed, including a decrease in sperm motility and concentration, and alterations in the migration of sperm cytoplasmic droplet. Testosterone levels and cellular proliferative activity did not change. Aging causes a morphological alteration of hamster
epididymis
(mainly in the cauda), and a decrease in sperm quality.
Anat
Rec
1999 12 01
PMID:Age-related changes in the hamster epididymis. 1058 20
Seasonal changes in the hypothalamo-pituitary-testes axis of the Japanese wood mice (Apodemus speciosus) were studied. The testes,
epididymis
, pituitary and hypothalamus were compared between mice in the breeding season (July) and non-breeding season (October) using morphological techniques, and the plasma testosterone level was evaluated by enzyme immunoassay. Significant differences in these tissues were observed between the breeding season and the non-breeding season. Specifically, differences in the non-breeding season included 1) a decline in testicular and epididymal weights, arrest of spermatogenesis and decrease of serum testosterone concentration; 2) a decrease in the number of luteinizing hormone (LH)-, follicle stimulating hormone (FSH)-, prolactin (PRL)-, and growth hormone (GH)-immunoreactive cells, and decrease in the size of FSH, PRL, and GH-immunoreactive cells; and 3) an increase in the size of gonadotropin-releasing hormone (GnRH)-immunoreactive neurons. Our findings indicate that the male adult Japanese wood mouse exhibits unique seasonal changes in the hypothalamo-pituitary-testes axis which are not found in laboratory mice.
Anat
Rec
2000 12 01
PMID:Seasonal changes in the hypothalamo-pituitary-testes axis of the Japanese wood mouse (Apodemus speciosus). 1107 1
The reproductive organs of Florida manatees (Trichechus manatus latirostris) are surrounded by thermogenic locomotory muscles and insulating fat. Manatees are reported to maintain core body temperatures of 35.6 degrees -36.4 degrees C, temperatures known to interfere with production and maturation of viable sperm in terrestrial mammals. We describe two novel venous plexuses associated with the manatee
epididymis
. Each
epididymis
is located in a hypogastric fossa at the caudolateral extremity of the abdominal cavity. Each hypogastric fossa is lined by an inguinal venous plexus that receives cooled blood from a superficial thoracocaudal plexus. We conclude that male manatees may prevent hyperthermic insult to their reproductive tissues by feeding cooled superficial blood to venous plexuses deep within their bodies. Female manatees also possess hypogastric fossae and venous structures similar to those found in male manatees. The ovaries, uterine tubes, and distal tips of the uterine horns are located in the hypogastric fossae. We suggest that the thermovascular structures we describe also prevent hypothermic insult to female manatee reproductive tissues. The venous structures in manatees are functionally similar to structures associated with reproductive thermoregulation in cetaceans and phocid seals. Thus, these thermovascular structures appear to be convergent morphological adaptations that occur in three clades of diving mammals with independent evolutionary histories.
Anat
Rec
2001 12 01
PMID:Functional morphology of venous structures associated with the male and female reproductive systems in Florida manatees (Trichechus manatus latirostris). 1174 89
The microvasculature of the water buffalo (Bubalus bubalis)
epididymis
was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo
epididymis
showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo
epididymis
plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo
epididymis
, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium.
Anat
Rec
2002 01 01
PMID:Microvasculature of the buffalo epididymis. 1174 72
Using immunohistochemical methods, we studied the cell-type- and species-specific expressions of estrogen receptor (ER) isoforms (ER alpha and ER beta) and androgen receptors (ARs) in the male reproductive tract and accessory sex glands of mature mice and rats. ER alpha and ER beta showed cell-type- and species-specific distributions, respectively. In contrast, AR was localized in the epithelial and stroma cells of all tissues examined in this study, in both species. In mice, the epithelial cells of the ductuli efferentes showed a strong ER alpha-immunoreaction, and those of the caput
epididymis
, coagulating glands, and prostate also exhibited a positive reaction. Stroma cells, except in the ductuli efferentes, showed a positive ER alpha-immunostaining. In rats, ER alpha was detected in very few cell types: the epithelial cells of the ductuli efferentes showed a strong reaction, and the stroma cells of the ampullary and urethral glands exhibited a weak reaction. ER beta was localized in the epithelial cells of the prostate in mice, while the reaction was faint or negative in both the epithelial and stroma cells of other tissues. In rats, the ER beta-immunoreaction was strongest in the epithelial cells of the ventral prostate. The epithelial cells of the corpus and cauda
epididymis
, ductus deferens, and urethral glands, and the stroma cells of the urethral glands were also positively ER beta-immunostained. Almost the same AR distribution pattern was observed in both species. In particular, strong AR-immunostaining was present in the epithelial cells of the caput and corpus
epididymis
, seminal vesicle, and ventral prostate. These results indicate that species and tissues differences should be taken into careful consideration in assessing the physiological and pharmacological effects of sex steroids (particularly estrogens) on the reproductive tissues of male rodents.
Anat
Rec
A Discov Mol Cell Evol Biol 2004 Aug
PMID:Localization of estrogen and androgen receptors in male reproductive tissues of mice and rats. 1527 48
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